Enhance EInkDisplayHandler and LVGLHandler with deep sleep functionality and partial refresh improvements

- Initialize LVGL with appropriate configuration and error handling.
- Create and initialize UIHandler to manage app icons and interactions.
- Register DemoApp and ShutdownApp with AppRegistry.
- Implement touch task and display initialization for EInkDisplayHandler.
- Handle shutdown signal by switching to ShutdownApp and performing cleanup.

main/display/display.cpp.old

@@ -0,0 +1,199 @@
+#include "display/display.h"
+#include "common/constants.h"
+#include "esp_log.h"
+#include "esp_lcd_touch_gt911.h"
+
+#define BUSY_ACTIVE_LEVEL   0  // BUSY pin is active low
+#define BUSY_INACTIVE_LEVEL 1
+
+DisplayHandler::~DisplayHandler() {
+  if (_spi_mutex != nullptr) {
+    vSemaphoreDelete(_spi_mutex);
+  }
+  if (_spi != nullptr) {
+    spi_bus_remove_device(_spi);
+  }
+  if (_tp_handle != nullptr) {
+    esp_lcd_touch_del(_tp_handle);
+  }
+  if (_tp_io_handle != nullptr) {
+    esp_lcd_panel_io_del(_tp_io_handle);
+  }
+}
+
+void DisplayHandler::init_devices(bool set_display_ready /*= true*/) {
+  ESP_LOGI("DisplayHandler", "Initializing display and touch...");
+  _epd_init();
+  _touch_init();
+  ESP_LOGI("DisplayHandler", "Display and touch initialized.");
+  if (set_display_ready) {
+    ESP_LOGI("DisplayHandler", "Setting display ready bit.");
+    xEventGroupSetBits(_system_event_group, DISPLAY_READY_BIT | TOUCH_CALIBRATED_BIT);
+  }
+}
+
+
+void DisplayHandler::epd_write_cmd(uint8_t cmd) {
+  ESP_LOGI("DisplayHandler", "epd_write_cmd: waiting to send 0x%02X", cmd);
+  if (xSemaphoreTake(_spi_mutex, pdMS_TO_TICKS(5000)) != pdTRUE) {
+    ESP_LOGE("DisplayHandler", "SPI mutex timeout for cmd 0x%02X", cmd);
+    return;
+  }
+  _dangerous_epd_write_cmd_without_lock(cmd);
+  xSemaphoreGive(_spi_mutex);
+  ESP_LOGI("DisplayHandler", "epd_write_cmd: 0x%02X done", cmd);
+}
+
+void DisplayHandler::epd_write_data(uint8_t data) {
+  ESP_LOGI("DisplayHandler", "epd_write_data: waiting to send 0x%02X", data);
+  if (xSemaphoreTake(_spi_mutex, pdMS_TO_TICKS(5000)) != pdTRUE) {
+    ESP_LOGE("DisplayHandler", "SPI mutex timeout for data 0x%02X", data);
+    return;
+  }
+  _dangerous_epd_write_data_without_lock(data);
+  xSemaphoreGive(_spi_mutex);
+  ESP_LOGI("DisplayHandler", "epd_write_data: 0x%02X done", data);
+}
+
+void DisplayHandler::epd_write_cmd_with_data(uint8_t cmd, const uint8_t* data, size_t data_len) {
+  ESP_LOGI("DisplayHandler", "epd_write_cmd_with_data: waiting to send cmd 0x%02X with %u bytes of data", cmd, (unsigned)data_len);
+  if (xSemaphoreTake(_spi_mutex, pdMS_TO_TICKS(5000)) != pdTRUE) {
+    ESP_LOGE("DisplayHandler", "SPI mutex timeout for cmd with data 0x%02X", cmd);
+    return;
+  }
+  _dangerous_epd_write_cmd_without_lock(cmd);
+  for (size_t i = 0; i < data_len; ++i) {
+    _dangerous_epd_write_data_without_lock(data[i]);
+  }
+  xSemaphoreGive(_spi_mutex);
+  ESP_LOGI("DisplayHandler", "epd_write_cmd_with_data: cmd 0x%02X with %u bytes of data done", cmd, (unsigned)data_len);
+}
+
+//
+// Private methods
+//
+
+void DisplayHandler::_dangerous_epd_write_cmd_without_lock(uint8_t cmd) {
+  ESP_LOGI("DisplayHandler", "_dangerous_epd_write_cmd_without_lock: sending 0x%02X", cmd);
+  gpio_set_level(PIN_DC, 0); // Command mode
+  spi_transaction_t t {};
+  t.length = 8;t.tx_buffer = &cmd;
+  esp_err_t err = spi_device_polling_transmit(_spi, &t);
+  if (err != ESP_OK) {
+    ESP_LOGE("DisplayHandler", "Failed to send data 0x%02X", cmd);
+  } else {
+    ESP_LOGI("DisplayHandler", "_dangerous_epd_write_cmd_without_lock: 0x%02X sent", cmd);
+  }
+}
+
+void DisplayHandler::_dangerous_epd_write_data_without_lock(uint8_t data) {
+  ESP_LOGI("DisplayHandler", "_dangerous_epd_write_data_without_lock: sending 0x%02X", data);
+  gpio_set_level(PIN_DC, 1); // Data mode
+  spi_transaction_t t = { };
+  t.length = 8; t.tx_buffer = &data;
+  esp_err_t err = spi_device_polling_transmit(_spi, &t);
+  if (err != ESP_OK) {
+    ESP_LOGE("DisplayHandler", "Failed to send data 0x%02X", data);
+  } else {
+    ESP_LOGI("DisplayHandler", "_dangerous_epd_write_data_without_lock: 0x%02X sent", data);
+  }
+}
+
+// required to be called by inheriting class after SPI device is created
+void DisplayHandler::_epd_init(void) {
+  ESP_LOGI("DisplayHandler", "Initializing EPD...");
+  // 1. Hardware Reset
+  gpio_set_level(PIN_RST, 0);
+  vTaskDelay(pdMS_TO_TICKS(10));
+  gpio_set_level(PIN_RST, 1);
+  vTaskDelay(pdMS_TO_TICKS(10));
+
+  // 2. Initialization Sequence
+  const uint8_t panel_setting_data[] = { 0x1F };
+  epd_write_cmd_with_data(0x00, panel_setting_data, 1); // Panel Setting
+  vTaskDelay(pdMS_TO_TICKS(10));
+  const uint8_t vcom_data[] = { 0x10, 0x07 };
+  epd_write_cmd_with_data(0x50, vcom_data, 2); // VCOM
+  vTaskDelay(pdMS_TO_TICKS(10));
+  epd_write_cmd(0x04); // Power ON
+  vTaskDelay(pdMS_TO_TICKS(100)); // Wait for power on
+
+  // Check BUSY pin with detailed logging
+  ESP_LOGI("DisplayHandler", "Waiting for EPD to be ready after power on...");
+  ESP_LOGI("DisplayHandler", "BUSY pin level after power on: %d (0=BUSY, 1=FREE)", gpio_get_level(PIN_BUSY));
+
+  int busy_timeout = 0;
+  while (gpio_get_level(PIN_BUSY) == BUSY_ACTIVE_LEVEL) {  // BUSY is active LOW
+    vTaskDelay(pdMS_TO_TICKS(10));
+    busy_timeout++;
+    if (busy_timeout > 500) {  // 5 second timeout
+      ESP_LOGE("DisplayHandler", "EPD power on timeout! BUSY pin stuck at 0");
+      break;
+    }
+    if (busy_timeout % 50 == 0) {  // Log every 500ms
+      ESP_LOGW("DisplayHandler", "Still waiting for EPD power on, timeout: %d/500", busy_timeout);
+    }
+  }
+  ESP_LOGI("DisplayHandler", "EPD power on complete after %d * 10ms, BUSY pin: %d", busy_timeout, gpio_get_level(PIN_BUSY));
+  const uint8_t booster_data[] = { 0x27, 0x27, 0x18, 0x17 };
+  epd_write_cmd_with_data(0x06, booster_data, 4); // Booster Soft Start
+  vTaskDelay(pdMS_TO_TICKS(10));
+
+  // Enhanced display drive commands
+  const uint8_t e0_data[] = { 0x02 };
+  epd_write_cmd_with_data(0xE0, e0_data, 1);
+  const uint8_t e5_data[] = { 0x5A };
+  epd_write_cmd_with_data(0xE5, e5_data, 1);
+}
+
+void DisplayHandler::_touch_init(void) {
+  ESP_LOGI("DisplayHandler", "Initializing touch...");
+
+  // 1. Initialize I2C Bus
+  i2c_config_t conf = {};
+  conf.mode = I2C_MODE_MASTER;
+  conf.sda_io_num = PIN_TOUCH_SDA;
+  conf.scl_io_num = PIN_TOUCH_SCL;
+  conf.sda_pullup_en = GPIO_PULLUP_ENABLE;
+  conf.scl_pullup_en = GPIO_PULLUP_ENABLE;
+  conf.master.clk_speed = 400000;
+
+  i2c_param_config(I2C_NUM_0, &conf);
+  i2c_driver_install(I2C_NUM_0, I2C_MODE_MASTER, 0, 0, 0);
+  ESP_LOGI("DisplayHandler", "I2C driver installed");
+
+  // 2. Initialize GT911
+  ESP_LOGI("DisplayHandler", "Initializing GT911 touch controller...");
+  esp_lcd_panel_io_i2c_config_t tp_io_config = {};
+  // temporarily disable -Wmissing-field-initializers, as ESP_LCD_TOUCH_IO_I2C_GT911_CONFIG macro does not set all fields
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wmissing-field-initializers"
+  esp_lcd_panel_io_i2c_config_t default_tp_io_config = ESP_LCD_TOUCH_IO_I2C_GT911_CONFIG();
+#pragma GCC diagnostic pop
+  tp_io_config.dev_addr = default_tp_io_config.dev_addr;
+  tp_io_config.control_phase_bytes = default_tp_io_config.control_phase_bytes;
+  tp_io_config.dc_bit_offset = default_tp_io_config.dc_bit_offset;
+  tp_io_config.lcd_cmd_bits = default_tp_io_config.lcd_cmd_bits;
+  tp_io_config.flags = default_tp_io_config.flags;
+  esp_lcd_new_panel_io_i2c(I2C_NUM_0, &tp_io_config, &_tp_io_handle);
+
+  // GT911-specific config with I2C address (0x5D = INT low during reset)
+  static esp_lcd_touch_io_gt911_config_t gt911_config = {
+    .dev_addr = ESP_LCD_TOUCH_IO_I2C_GT911_ADDRESS  // 0x5D
+  };
+
+  esp_lcd_touch_config_t tp_cfg = {};
+  tp_cfg.x_max = 800;
+  tp_cfg.y_max = 480;
+  tp_cfg.rst_gpio_num = PIN_TOUCH_RST;
+  tp_cfg.int_gpio_num = PIN_TOUCH_IRQ;
+  tp_cfg.driver_data = &gt911_config;  // Pass GT911-specific config for automatic reset
+
+  esp_err_t touch_ret = esp_lcd_touch_new_i2c_gt911(_tp_io_handle, &tp_cfg, &_tp_handle);
+  if (touch_ret == ESP_OK && _tp_handle != nullptr) {
+    ESP_LOGI("DisplayHandler", "GT911 touch controller initialized successfully");
+  } else {
+    ESP_LOGE("DisplayHandler", "GT911 touch controller initialization failed: %s", esp_err_to_name(touch_ret));
+    _tp_handle = nullptr;
+  }
+}

main/display/display.h.old

@@ -0,0 +1,42 @@
+#pragma once
+#include "driver/spi_master.h"
+#include "driver/gpio.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "esp_lcd_touch_gt911.h"
+#include "display/constants.h"
+#include <driver/i2c.h>
+
+class DisplayHandler {
+public:
+  DisplayHandler(
+    EventGroupHandle_t system_event_group
+  ) : _system_event_group(system_event_group) { }
+  virtual ~DisplayHandler();
+  
+  // required to be called by inheriting class after SPI device is created
+  // set set_display_ready to false if further initialization is needed before marking display ready
+  virtual void init_devices(bool set_display_ready = true);
+
+protected:
+  // Allow derived classes to access touch handle
+  esp_lcd_touch_handle_t get_touch_handle() const { return _tp_handle; }
+
+  void epd_write_cmd(uint8_t cmd);
+  void epd_write_data(uint8_t data);
+
+  void epd_write_cmd_with_data(uint8_t cmd, const uint8_t* data, size_t data_len);
+
+protected:
+  SemaphoreHandle_t _spi_mutex = xSemaphoreCreateMutex();
+  spi_device_handle_t _spi = nullptr;
+  EventGroupHandle_t _system_event_group = nullptr;
+  esp_lcd_panel_io_handle_t _tp_io_handle = nullptr;
+  esp_lcd_touch_handle_t _tp_handle = nullptr;
+
+  void _dangerous_epd_write_cmd_without_lock(uint8_t cmd);
+  void _dangerous_epd_write_data_without_lock(uint8_t data);
+
+  void _epd_init(void);
+  void _touch_init(void);
+};

main/display/eink_display_handler.cpp

@@ -11,53 +11,48 @@
 #define DISPLAY_BUFFER_SIZE (EINK_HEIGHT* EINK_WIDTH) / 8 // 1 bit per pixels
 #define MINIMUM_PIN_SETUP_DELAY_MS 10
 #define MINIMUM_POWER_ON_DELAY_MS 100
-#define PARTIAL_REFRESH_THRESHOLD 5  // Full refresh every N partial refreshes
+#define BUSY_ACTIVE_LEVEL   0  // BUSY pin is active low
+#define BUSY_INACTIVE_LEVEL 1
+#define DMA_TRANSFER_CHUNK_SIZE 4096  // 4KB chunk size for DMA transfers
 
-static uint8_t* DRAW_BUFFER; // 1 bit per pixel
-static uint8_t* OLD_DRAW_BUFFER; // 1 bit per pixel
-static uint8_t* black_data;
-static uint8_t* white_data;
+static uint8_t white_data[DISPLAY_BUFFER_SIZE]; // all white data
+static uint8_t black_data[DISPLAY_BUFFER_SIZE]; // all black data
 
 EInkDisplayHandler::EInkDisplayHandler() {
-  black_data = static_cast<uint8_t*>(heap_caps_malloc(DISPLAY_BUFFER_SIZE, MALLOC_CAP_SPIRAM));
-  white_data = static_cast<uint8_t*>(heap_caps_malloc(DISPLAY_BUFFER_SIZE, MALLOC_CAP_SPIRAM));
-  DRAW_BUFFER = static_cast<uint8_t*>(heap_caps_malloc(DISPLAY_BUFFER_SIZE, MALLOC_CAP_SPIRAM));
-  OLD_DRAW_BUFFER = static_cast<uint8_t*>(heap_caps_malloc(DISPLAY_BUFFER_SIZE, MALLOC_CAP_SPIRAM));
-  memset(black_data, 0xFF, DISPLAY_BUFFER_SIZE); // eink uses 1 for black
-  memset(white_data, 0x00, DISPLAY_BUFFER_SIZE);
-  memset(DRAW_BUFFER, 0x00, DISPLAY_BUFFER_SIZE); // start with all white (0 = white in e-ink)
-  memset(OLD_DRAW_BUFFER, 0x00, DISPLAY_BUFFER_SIZE); // start with all white (0 = white in e-ink)
-  draw_buffer_ = DRAW_BUFFER;
-  old_buffer_ = OLD_DRAW_BUFFER;
-
+  memset(white_data, 0xFF, sizeof(white_data));
+  memset(black_data, 0x00, sizeof(black_data));
+  spi_mutex_ = xSemaphoreCreateMutex();
+  if (spi_mutex_ == nullptr) {
+    ESP_LOGE(TAG, "Failed to create SPI mutex");
+  }
+  spi_transaction_mutex_ = xSemaphoreCreateMutex();
+  if (spi_transaction_mutex_ == nullptr) {
+    ESP_LOGE(TAG, "Failed to create SPI transaction mutex");
+  }
   refresh_mutex_ = xSemaphoreCreateMutex();
   if (refresh_mutex_ == nullptr) {
     ESP_LOGE(TAG, "Failed to create refresh mutex");
   }
 }
-
 EInkDisplayHandler::~EInkDisplayHandler() {
+  if (spi_mutex_ != nullptr) {
+    vSemaphoreDelete(spi_mutex_);
+  }
+  if (spi_transaction_mutex_ != nullptr) {
+    vSemaphoreDelete(spi_transaction_mutex_);
+  }
   if (refresh_mutex_ != nullptr) {
     vSemaphoreDelete(refresh_mutex_);
   }
+  if (spi_ != nullptr) {
+    spi_bus_remove_device(spi_);
+  }
   if (tp_handle_ != nullptr) {
     esp_lcd_touch_del(tp_handle_);
   }
   if (tp_io_handle_ != nullptr) {
     esp_lcd_panel_io_del(tp_io_handle_);
   }
-  if (black_data != nullptr) {
-    heap_caps_free(black_data);
-  }
-  if (white_data != nullptr) {
-    heap_caps_free(white_data);
-  }
-  if (DRAW_BUFFER != nullptr) {
-    heap_caps_free(DRAW_BUFFER);
-  }
-  if (OLD_DRAW_BUFFER != nullptr) {
-    heap_caps_free(OLD_DRAW_BUFFER);
-  }
 }
 
 esp_err_t EInkDisplayHandler::deep_sleep_display(void) {
@@ -68,26 +63,26 @@ esp_err_t EInkDisplayHandler::deep_sleep_display(void) {
   }
   {
     esp_err_t err = ESP_OK;
-    TransactionGuard transaction_guard(this->epd_handler_);
+    TransactionGuard transaction_guard(*this);
     err = transaction_guard.begin(pdMS_TO_TICKS(5000));
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to begin transaction for deep sleep: %s", esp_err_to_name(err));
       return err;
     }
-    epd_handler_.wait_for_idle();
+    wait_for_idle();
 
-    err = epd_handler_.epd_write_cmd(0x02, transaction_guard.transaction_id()); // power off
+    err = epd_write_cmd(0x02, transaction_guard.transaction_id()); // power off
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to send power off command: %s", esp_err_to_name(err));
       return err;
     }
-    epd_handler_.wait_for_idle();
-    err = epd_handler_.epd_write_cmd(0x07, transaction_guard.transaction_id());   //deep sleep
+    wait_for_idle();
+    err = epd_write_cmd(0x07, transaction_guard.transaction_id());   //deep sleep
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to send deep sleep command: %s", esp_err_to_name(err));
       return err;
     }
-    err = epd_handler_.epd_write_data(0xA5, transaction_guard.transaction_id());
+    err = epd_write_data(0xA5, transaction_guard.transaction_id());
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to send deep sleep data: %s", esp_err_to_name(err));
       return err;
@@ -100,43 +95,32 @@ esp_err_t EInkDisplayHandler::deep_sleep_display(void) {
 esp_err_t EInkDisplayHandler::refresh_display() {
   esp_err_t err = ESP_OK;
 
-
   if (is_deep_sleep_) {
-
-    err = full_write(draw_buffer_, true);
-    if (err != ESP_OK) {
-      ESP_LOGE(TAG, "Full write failed during refresh_display: %s", esp_err_to_name(err));
-      return err;
+    epd_init_();
   }
-  } else {
-    // refresh does not correctly work after recovering from deep sleep due to sram reset
+
   {
     ESP_LOGI(TAG, "Waiting for display to be idle...");
-      TransactionGuard transaction_guard(this->epd_handler_);
+    TransactionGuard transaction_guard(*this);
     err = transaction_guard.begin(pdMS_TO_TICKS(10000));
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to begin transaction for display refresh: %s", esp_err_to_name(err));
       return err;
     }
-      if (is_deep_sleep_) {
-        epd_init_internal_(transaction_guard.transaction_id());
-      }
-
-      epd_handler_.wait_for_idle();
+    wait_for_idle();
     ESP_LOGI(TAG, "Starting display refresh...");
-      err = epd_handler_.epd_write_cmd(0x92, transaction_guard.transaction_id()); // enter normal mode
+    err = epd_write_cmd(0x92, transaction_guard.transaction_id()); // enter normal mode
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to enter normal mode: %s", esp_err_to_name(err));
       return err;
     }
-      err = epd_handler_.epd_write_cmd(0x12, transaction_guard.transaction_id()); // display refresh
+    err = epd_write_cmd(0x12, transaction_guard.transaction_id()); // display refresh
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to send display refresh command: %s", esp_err_to_name(err));
       return err;
     }
     vTaskDelay(pdMS_TO_TICKS(MINIMUM_PIN_SETUP_DELAY_MS)); // at least 200us delay
-      epd_handler_.wait_for_idle();
-    }
+    wait_for_idle();
   }
 
   {
@@ -149,6 +133,12 @@ esp_err_t EInkDisplayHandler::refresh_display() {
     force_full_refresh_ = false;
   }
 
+  err = deep_sleep_display();
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "Failed to enter deep sleep after refresh: %s", esp_err_to_name(err));
+    return err;
+  }
+
   ESP_LOGI(TAG, "Refresh complete");
   return ESP_OK;
 }
@@ -157,35 +147,33 @@ esp_err_t EInkDisplayHandler::full_write(const uint8_t* framebuffer, const bool
   ESP_LOGI(TAG, "Starting full refresh (3 seconds)...");
   esp_err_t err = ESP_OK;
 
+  if (is_deep_sleep_) {
+    epd_init_();
+  }
 
   {
-    TransactionGuard transaction_guard(this->epd_handler_);
+    TransactionGuard transaction_guard(*this);
     err = transaction_guard.begin(pdMS_TO_TICKS(10000));
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to begin transaction for full refresh: %s", esp_err_to_name(err));
       return err;
     }
-    if (is_deep_sleep_) {
-      epd_init_internal_(transaction_guard.transaction_id());
-    }
 
-    write_to_buffer_(framebuffer, RefreshArea { 0, 0, DISPLAY_WIDTH - 1,  DISPLAY_HEIGHT - 1 });
-
-    epd_handler_.wait_for_idle();
+    wait_for_idle();
     // Step 0: Enter normal mode
-    err = epd_handler_.epd_write_cmd(0x92, transaction_guard.transaction_id()); // enter normal mode
+    err = epd_write_cmd(0x92, transaction_guard.transaction_id()); // enter normal mode
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to enter normal mode: %s", esp_err_to_name(err));
       return err;
     }
     // Step 1: Write old data (0x10) - Arduino uses 0xFF (all white) for base map
     {
-      err = epd_handler_.epd_write_cmd(0x10, transaction_guard.transaction_id());
+      err = epd_write_cmd(0x10, transaction_guard.transaction_id());
       if (err != ESP_OK) {
         ESP_LOGE(TAG, "Failed to send old data command: %s", esp_err_to_name(err));
         return err;
       }
-      err = epd_handler_.transfer_spi_data(white_basemap ? black_data : white_data, DISPLAY_BUFFER_SIZE, transaction_guard.transaction_id()); // Send all white data (0xFF)
+      err = transfer_spi_data(white_basemap ? white_data : black_data, DISPLAY_BUFFER_SIZE, transaction_guard.transaction_id()); // Send all white data (0xFF)
       if (err != ESP_OK) {
         ESP_LOGE(TAG, "Failed to send all white data for old data: %s", esp_err_to_name(err));
         return err;
@@ -194,20 +182,20 @@ esp_err_t EInkDisplayHandler::full_write(const uint8_t* framebuffer, const bool
 
     // Step 2: Write new data (0x13)
     {
-      err = epd_handler_.epd_write_cmd(0x13, transaction_guard.transaction_id());
+      err = epd_write_cmd(0x13, transaction_guard.transaction_id());
       if (err != ESP_OK) {
         ESP_LOGE(TAG, "Failed to send new data command: %s", esp_err_to_name(err));
         return err;
       }
 
-      err = epd_handler_.transfer_spi_data(draw_buffer_, DISPLAY_BUFFER_SIZE, transaction_guard.transaction_id()); // Send new framebuffer data
+      err = transfer_spi_data(framebuffer, DISPLAY_BUFFER_SIZE, transaction_guard.transaction_id()); // Send new framebuffer data
       if (err != ESP_OK) {
         ESP_LOGE(TAG, "Failed to send framebuffer data for new data: %s", esp_err_to_name(err));
         return err;
       }
     }
     // Step 3: Trigger display refresh (DRF)
-    err = epd_handler_.epd_write_cmd(0x12, transaction_guard.transaction_id());
+    err = epd_write_cmd(0x12, transaction_guard.transaction_id());
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to send display refresh command: %s", esp_err_to_name(err));
       return err;
@@ -217,7 +205,7 @@ esp_err_t EInkDisplayHandler::full_write(const uint8_t* framebuffer, const bool
     ESP_LOGI(TAG, "Display refresh triggered, BUSY pin: %d", gpio_get_level(PIN_BUSY));
 
     // Wait for refresh to complete
-    epd_handler_.wait_for_idle();
+    wait_for_idle();
   }
 
   err = deep_sleep_display();
@@ -226,96 +214,57 @@ esp_err_t EInkDisplayHandler::full_write(const uint8_t* framebuffer, const bool
     return err;
   }
 
-  refresh_area_.reset();
-  memcpy(old_buffer_, draw_buffer_, DISPLAY_BUFFER_SIZE);
-
   ESP_LOGI(TAG, "Full refresh complete");
   return ESP_OK;
 }
 
-// TODO: Partial refresh is inverted in color
-esp_err_t EInkDisplayHandler::partial_refresh(const uint8_t* incoming_partial_framebuffer, const RefreshArea& incoming_area, const bool is_last_partial_update) {
+esp_err_t EInkDisplayHandler::partial_refresh(const uint8_t* partial_framebuffer, const RefreshArea& area) {
   ESP_LOGI(TAG, "Starting partial refresh (0.3 seconds)...");
   esp_err_t err = ESP_OK;
 
-  write_to_buffer_(incoming_partial_framebuffer, incoming_area);
-
-  // Always expand refresh_area_ to include incoming_area
-  refresh_area_.expand_to_include(incoming_area);
-
-  if (!is_last_partial_update) {
-    ESP_LOGI(TAG, "Partial refresh skipped (not last partial update)");
-    return ESP_OK;
-  }
-
-  {
-    TransactionGuard transaction_guard(this->epd_handler_);
-    err = transaction_guard.begin(pdMS_TO_TICKS(5000));
-    if (err != ESP_OK) {
-      ESP_LOGE(TAG, "Failed to begin transaction for partial refresh: %s", esp_err_to_name(err));
-      return err;
-    }
-    // Wake display from deep sleep INSIDE the transaction to prevent race conditions
-    if (is_deep_sleep_) {
-      err = epd_init_internal_(transaction_guard.transaction_id());
-      if (err != ESP_OK) {
-        ESP_LOGE(TAG, "Failed to initialize EPD for partial refresh: %s", esp_err_to_name(err));
-        return err;
-      }
-      err = refresh_old_buffer_(transaction_guard.transaction_id());
-      if (err != ESP_OK) {
-        ESP_LOGE(TAG, "Failed to refresh old buffer during partial refresh init: %s", esp_err_to_name(err));
-        return err;
-      }
-    }
-
-
-    RefreshArea area = refresh_area_;
-    if (area.x1 % 8 != 0 || area.x2 % 8 != 7) {
-      ESP_LOGE(TAG, "Partial refresh area x1 and x2 must be byte-aligned (x1 %% 8 == 0 and x2 %% 8 == 7)");
-      ESP_LOGI(TAG, "Given area: x1=%d, x2=%d", area.x1, area.x2);
-      return ESP_ERR_INVALID_ARG;
-    }
-
   // Calculate partial buffer size based on the refresh area
   const uint32_t area_width_bytes = (area.x2 - area.x1 + 1) / 8;
   const uint32_t area_height = area.y2 - area.y1 + 1;
   const size_t partial_buffer_size = area_width_bytes * area_height;
 
-    // uint8_t* partial_buffer = new uint8_t[partial_buffer_size];
-    uint8_t* partial_buffer = static_cast<uint8_t*>(heap_caps_malloc(partial_buffer_size, MALLOC_CAP_DMA | MALLOC_CAP_INTERNAL));
-
-    if (partial_buffer == nullptr) {
-      ESP_LOGE(TAG, "Failed to allocate partial buffer for partial refresh");
-      return ESP_ERR_NO_MEM;
-    }
-    // Copy the relevant area from draw_buffer_ to partial_buffer
-    for (int32_t row = 0; row < area_height; ++row) {
-      uint32_t fb_y = area.y1 + row;
-      uint32_t fb_x_byte_start = area.x1 / 8;
-      uint8_t* fb_ptr = &draw_buffer_[fb_y * (DISPLAY_WIDTH / 8) + fb_x_byte_start];
-      uint8_t* dest_ptr = &partial_buffer[row * area_width_bytes];
-      memcpy(dest_ptr, fb_ptr, area_width_bytes);
+  {
+    TransactionGuard transaction_guard(*this);
+    err = transaction_guard.begin(pdMS_TO_TICKS(5000));
+    if (err != ESP_OK) {
+      ESP_LOGE(TAG, "Failed to begin transaction for partial refresh: %s", esp_err_to_name(err));
+      return err;
     }
 
+    // Wake display from deep sleep INSIDE the transaction to prevent race conditions
+    if (is_deep_sleep_) {
+      err = epd_init_partial_internal_(transaction_guard.transaction_id());
+      if (err != ESP_OK) {
+        ESP_LOGE(TAG, "Failed to initialize EPD for partial refresh: %s", esp_err_to_name(err));
+        return err;
+      }
+    }
 
-    epd_handler_.wait_for_idle();
+    wait_for_idle();
 
     // Step 1 VCOM setting
     std::vector<uint8_t> vcom_data = { 0xA9, 0x07 };
-    err = epd_handler_.epd_write_cmd_with_data(0x50, vcom_data, transaction_guard.transaction_id()); // VCOM for partial refresh
+    err = epd_write_cmd_with_data(0x50, vcom_data, transaction_guard.transaction_id()); // VCOM for partial refresh
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to set VCOM for partial refresh: %s", esp_err_to_name(err));
       return err;
     }
     // Step 2: Enter partial refresh mode
-    err = epd_handler_.epd_write_cmd(0x91, transaction_guard.transaction_id());  // Enter partial mode
+    err = epd_write_cmd(0x91, transaction_guard.transaction_id());  // Enter partial mode
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to enter partial refresh mode: %s", esp_err_to_name(err));
       return err;
     }
     // Step 3: Set partial window
     {
+      if (area.x1 % 8 != 0 || area.x2 % 8 != 7) {
+        ESP_LOGE(TAG, "Partial refresh area x1 and x2 must be byte-aligned (x1 %% 8 == 0 and x2 %% 8 == 7)");
+        return ESP_ERR_INVALID_ARG;
+      }
       // ------DD
       // DDDDD000
       // ------DD
@@ -353,41 +302,33 @@ esp_err_t EInkDisplayHandler::partial_refresh(const uint8_t* incoming_partial_fr
       ESP_LOGI(TAG, "Partial window data: %02X %02X %02X %02X %02X %02X %02X %02X",
         window_data[0], window_data[1], window_data[2], window_data[3], window_data[4],
         window_data[5], window_data[6], window_data[7]);
-      err = epd_handler_.epd_write_cmd_with_data(0x90, window_data, transaction_guard.transaction_id());  // Set partial window
+      err = epd_write_cmd_with_data(0x90, window_data, transaction_guard.transaction_id());  // Set partial window
       if (err != ESP_OK) {
         ESP_LOGE(TAG, "Failed to send set partial window command: %s", esp_err_to_name(err));
         return err;
       }
     }
 
-    // Step 5: Write new data (0x13)
+    // Step 4: Write new data (0x13)
     {
-      err = epd_handler_.epd_write_cmd(0x13, transaction_guard.transaction_id());
+      err = epd_write_cmd(0x13, transaction_guard.transaction_id());
       if (err != ESP_OK) {
         ESP_LOGE(TAG, "Failed to send new data command for partial refresh: %s", esp_err_to_name(err));
-        heap_caps_free(partial_buffer);
         return err;
       }
 
       // Send only the partial area data, not the full display buffer
-      ESP_LOGI(TAG, "Sending new partial buffer: %zu bytes (area: %dx%d)",
+      ESP_LOGI(TAG, "Sending partial buffer: %zu bytes (area: %dx%d)",
         partial_buffer_size, area_width_bytes * 8, area_height);
-      err = epd_handler_.transfer_spi_data(partial_buffer, partial_buffer_size, transaction_guard.transaction_id(), true); // Inverted for partial refresh
+      err = transfer_spi_data(partial_framebuffer, partial_buffer_size, transaction_guard.transaction_id());
       if (err != ESP_OK) {
-        ESP_LOGE(TAG, "Failed to send partial_buffer data for partial refresh: %s", esp_err_to_name(err));
-        heap_caps_free(partial_buffer);
+        ESP_LOGE(TAG, "Failed to send partial_framebuffer data for partial refresh: %s", esp_err_to_name(err));
         return err;
       }
-
-      memcpy(old_buffer_, draw_buffer_, DISPLAY_BUFFER_SIZE);
     }
 
-    // Clean up partial buffer
-    heap_caps_free(partial_buffer);
-
-    // Step 6: Trigger partial display refresh (DRF)
-    // Use 0x12 (Display Update) command - same as full refresh, per sample code
-    err = epd_handler_.epd_write_cmd(0x12, transaction_guard.transaction_id());
+    // Step 5: Trigger partial display refresh (DRF) by ending the data write
+    err = epd_write_cmd(0x11, transaction_guard.transaction_id());
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to send display refresh command for partial refresh: %s", esp_err_to_name(err));
       return err;
@@ -395,22 +336,15 @@ esp_err_t EInkDisplayHandler::partial_refresh(const uint8_t* incoming_partial_fr
 
     vTaskDelay(pdMS_TO_TICKS(MINIMUM_PIN_SETUP_DELAY_MS)); // at least 200us delay
 
-    epd_handler_.wait_for_idle();
-    // Step 7: Exit partial mode
-    err = epd_handler_.epd_write_cmd(0x92, transaction_guard.transaction_id());
+    wait_for_idle();
+    // Step 6: Exit partial mode
+    err = epd_write_cmd(0x92, transaction_guard.transaction_id());
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to exit partial refresh mode: %s", esp_err_to_name(err));
       return err;
     }
   }
   ESP_LOGI(TAG, "Partial refresh complete");
-
-  err = deep_sleep_display();
-  if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to enter deep sleep after partial refresh: %s", esp_err_to_name(err));
-    return err;
-  }
-
   if (force_full_refresh_) {
     ESP_LOGI(TAG, "Full refresh already requested, skipping partial refresh count increment");
     err = refresh_display();
@@ -420,7 +354,6 @@ esp_err_t EInkDisplayHandler::partial_refresh(const uint8_t* incoming_partial_fr
     }
     return ESP_OK;
   }
-
   {
     SemaphoreGuard guard(refresh_mutex_);
     if (guard.take(pdMS_TO_TICKS(5000)) != pdTRUE) {
@@ -439,9 +372,11 @@ esp_err_t EInkDisplayHandler::partial_refresh(const uint8_t* incoming_partial_fr
     }
   }
 
-
-
-  refresh_area_.reset();
+  err = deep_sleep_display();
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "Failed to enter deep sleep after partial refresh: %s", esp_err_to_name(err));
+    return err;
+  }
 
   return ESP_OK;
 }
@@ -449,7 +384,7 @@ esp_err_t EInkDisplayHandler::partial_refresh(const uint8_t* incoming_partial_fr
 esp_err_t EInkDisplayHandler::clear_display(void) {
   ESP_LOGI(TAG, "Clearing display to all white...");
 
-  esp_err_t err = full_write(white_data, false);
+  esp_err_t err = full_write(black_data, false);
   if (err != ESP_OK) {
     ESP_LOGE(TAG, "Failed to clear display: %s", esp_err_to_name(err));
     return err;
@@ -458,19 +393,7 @@ esp_err_t EInkDisplayHandler::clear_display(void) {
   return ESP_OK;
 }
 
-void EInkDisplayHandler::write_to_buffer_(const uint8_t* src_buffer, const RefreshArea& area) {
-  // Copy the relevant area from src_buffer to draw_buffer_
-  const uint32_t area_width_bytes = (area.x2 - area.x1 + 1) / 8;
-  const uint32_t area_height = area.y2 - area.y1 + 1;
 
-  for (int32_t row = 0; row < area_height; ++row) {
-    uint32_t fb_y = area.y1 + row;
-    uint32_t fb_x_byte_start = area.x1 / 8;
-    const uint8_t* src_ptr = &src_buffer[row * area_width_bytes];
-    uint8_t* dest_ptr = &draw_buffer_[fb_y * (DISPLAY_WIDTH / 8) + fb_x_byte_start];
-    memcpy(dest_ptr, src_ptr, area_width_bytes);
-  }
-}
 
 // Request a full refresh on next flush
 void EInkDisplayHandler::request_full_refresh(void) {
@@ -484,6 +407,26 @@ void EInkDisplayHandler::request_full_refresh(void) {
   }
 }
 
+// Check if display is busy (refreshing)
+bool EInkDisplayHandler::is_busy(void) const {
+  return gpio_get_level(PIN_BUSY) == BUSY_ACTIVE_LEVEL;  // BUSY is active LOW
+}
+void EInkDisplayHandler::wait_for_idle(void) const {
+  ESP_LOGI(TAG, "Waiting for display ready (BUSY pin)...");
+  int initial_level = gpio_get_level(PIN_BUSY);
+  ESP_LOGI(TAG, "Initial BUSY pin level: %d (0=BUSY, 1=FREE)", initial_level);
+
+  // If already free, no need to wait
+  if (initial_level == BUSY_INACTIVE_LEVEL) {
+    ESP_LOGI(TAG, "Display already ready (BUSY pin = 1)");
+    return;
+  }
+  while (gpio_get_level(PIN_BUSY) != BUSY_INACTIVE_LEVEL) {
+    vTaskDelay(pdMS_TO_TICKS(10));
+  }
+  ESP_LOGI(TAG, "Display is now ready (BUSY pin = 1)");
+}
+
 
 esp_err_t EInkDisplayHandler::init_devices(EventGroupHandle_t system_event_group) {
   esp_err_t err;
@@ -492,9 +435,9 @@ esp_err_t EInkDisplayHandler::init_devices(EventGroupHandle_t system_event_group
     ESP_LOGE(TAG, "Failed to initialize display pins: %s", esp_err_to_name(err));
     return err;
   }
-  err = this->epd_handler_.init();
+  err = epd_init_();
   if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to initialize EPD handler: %s", esp_err_to_name(err));
+    ESP_LOGE(TAG, "Failed to initialize EPD: %s", esp_err_to_name(err));
     return err;
   }
   err = init_touch_();
@@ -502,6 +445,12 @@ esp_err_t EInkDisplayHandler::init_devices(EventGroupHandle_t system_event_group
     ESP_LOGE(TAG, "Failed to initialize touch: %s", esp_err_to_name(err));
     return err;
   }
+  err = deep_sleep_display();
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "Failed to put display into deep sleep: %s", esp_err_to_name(err));
+    return err;
+  }
+
   // if system_event_group is provided, set display ready bits
   if (system_event_group != nullptr) {
     // Indicate that display is ready
@@ -540,13 +489,50 @@ esp_err_t EInkDisplayHandler::init_display_pins_(void) {
     return ret;
   }
 
+  // Initialize SPI bus
+  spi_bus_config_t buscfg = {};
+  buscfg.mosi_io_num = 11;  // MOSI pin
+  buscfg.miso_io_num = -1;  // No MISO for e-paper
+  buscfg.sclk_io_num = 12;  // SCK pin
+  buscfg.quadwp_io_num = -1;
+  buscfg.quadhd_io_num = -1;
+  buscfg.max_transfer_sz = DISPLAY_BUFFER_SIZE;
+
+  ret = spi_bus_initialize(SPI2_HOST, &buscfg, SPI_DMA_CH_AUTO);
+  if (ret != ESP_OK) {
+    ESP_LOGE(TAG, "Failed to initialize SPI bus: %s", esp_err_to_name(ret));
+    return ret;
+  }
+
+  // Add SPI device
+  spi_device_interface_config_t devcfg = {};
+  devcfg.clock_speed_hz = 10 * 1000 * 1000;  // 10 MHz
+  devcfg.mode = 0;  // SPI mode 0
+  devcfg.spics_io_num = PIN_CS;
+  devcfg.queue_size = 7;  // Queue size for non-blocking transactions
+  devcfg.pre_cb = nullptr;
+
+  ret = spi_bus_add_device(SPI2_HOST, &devcfg, &spi_);
+  if (ret != ESP_OK) {
+    ESP_LOGE(TAG, "Failed to add SPI device: %s", esp_err_to_name(ret));
+    return ret;
+  }
   return ESP_OK;
 }
 
-esp_err_t EInkDisplayHandler::epd_init_internal_(uint32_t transaction_id) {
+
+// required to be called by inheriting class after SPI device is created
+esp_err_t EInkDisplayHandler::epd_init_(void) {
   ESP_LOGI(TAG, "Initializing EPD...");
   esp_err_t err;
 
+  {
+    TransactionGuard transaction_guard(*this);
+    esp_err_t begin_err = transaction_guard.begin();
+    if (begin_err != ESP_OK) {
+      ESP_LOGE(TAG, "Failed to begin transaction: %s", esp_err_to_name(begin_err));
+      return begin_err;
+    }
 
     // 1. Hardware Reset
     err = gpio_set_level(PIN_RST, 0);
@@ -564,20 +550,20 @@ esp_err_t EInkDisplayHandler::epd_init_internal_(uint32_t transaction_id) {
 
     // 2. Initialization Sequence
     std::vector<uint8_t> panel_setting_data = { 0x1F };
-  err = epd_handler_.epd_write_cmd_with_data(0x00, panel_setting_data, transaction_id); // Panel Setting
+    err = epd_write_cmd_with_data(0x00, panel_setting_data, transaction_guard.transaction_id()); // Panel Setting
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to send Panel Setting command: %s", esp_err_to_name(err));
       return err;
     }
     vTaskDelay(pdMS_TO_TICKS(MINIMUM_PIN_SETUP_DELAY_MS));
     std::vector<uint8_t> vcom_data = { 0x10, 0x07 };
-  err = epd_handler_.epd_write_cmd_with_data(0x50, vcom_data, transaction_id); // VCOM
+    err = epd_write_cmd_with_data(0x50, vcom_data, transaction_guard.transaction_id()); // VCOM
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to send VCOM command: %s", esp_err_to_name(err));
       return err;
     }
     vTaskDelay(pdMS_TO_TICKS(MINIMUM_PIN_SETUP_DELAY_MS));
-  err = epd_handler_.epd_write_cmd(0x04, transaction_id); // Power ON
+    err = epd_write_cmd(0x04, transaction_guard.transaction_id()); // Power ON
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to send Power ON command: %s", esp_err_to_name(err));
       return err;
@@ -588,9 +574,21 @@ esp_err_t EInkDisplayHandler::epd_init_internal_(uint32_t transaction_id) {
     ESP_LOGI(TAG, "Waiting for EPD to be ready after power on...");
     ESP_LOGI(TAG, "BUSY pin level after power on: %d (0=BUSY, 1=FREE)", gpio_get_level(PIN_BUSY));
 
-  epd_handler_.wait_for_idle();
+    int busy_timeout = 0;
+    while (gpio_get_level(PIN_BUSY) == BUSY_ACTIVE_LEVEL) {  // BUSY is active LOW
+      vTaskDelay(pdMS_TO_TICKS(MINIMUM_PIN_SETUP_DELAY_MS));
+      busy_timeout++;
+      if (busy_timeout > 500) {  // 5 second timeout
+        ESP_LOGE(TAG, "EPD power on timeout! BUSY pin stuck at 0");
+        return ESP_ERR_TIMEOUT;
+      }
+      if (busy_timeout % 50 == 0) {  // Log every 500ms
+        ESP_LOGW(TAG, "Still waiting for EPD power on, timeout: %d/500", busy_timeout);
+      }
+    }
+    ESP_LOGI(TAG, "EPD power on complete after %d * 10ms, BUSY pin: %d", busy_timeout, gpio_get_level(PIN_BUSY));
     std::vector<uint8_t> booster_data = { 0x27, 0x27, 0x18, 0x17 };
-  err = epd_handler_.epd_write_cmd_with_data(0x06, booster_data, transaction_id); // Booster Soft Start
+    err = epd_write_cmd_with_data(0x06, booster_data, transaction_guard.transaction_id()); // Booster Soft Start
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to send Booster Soft Start command: %s", esp_err_to_name(err));
       return err;
@@ -599,23 +597,32 @@ esp_err_t EInkDisplayHandler::epd_init_internal_(uint32_t transaction_id) {
 
     // Enhanced display drive commands
     std::vector<uint8_t> e0_data = { 0x02 };
-  err = epd_handler_.epd_write_cmd_with_data(0xE0, e0_data, transaction_id);
+    err = epd_write_cmd_with_data(0xE0, e0_data, transaction_guard.transaction_id());
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to send Enhanced Display Drive command: %s", esp_err_to_name(err));
       return err;
     }
     std::vector<uint8_t> e5_data = { 0x5A };
-  err = epd_handler_.epd_write_cmd_with_data(0xE5, e5_data, transaction_id);
+    err = epd_write_cmd_with_data(0xE5, e5_data, transaction_guard.transaction_id());
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Failed to send Enhanced Display Drive command: %s", esp_err_to_name(err));
       return err;
     }
-
+  }
   is_deep_sleep_ = false;
-
   return err;
 }
 
+esp_err_t EInkDisplayHandler::epd_init_partial_(void) {
+  TransactionGuard transaction_guard(*this);
+  esp_err_t begin_err = transaction_guard.begin();
+  if (begin_err != ESP_OK) {
+    ESP_LOGE(TAG, "Failed to begin transaction: %s", esp_err_to_name(begin_err));
+    return begin_err;
+  }
+  return epd_init_partial_internal_(transaction_guard.transaction_id());
+}
+
 // Internal version that uses an existing transaction (no separate TransactionGuard)
 esp_err_t EInkDisplayHandler::epd_init_partial_internal_(uint32_t transaction_id) {
   ESP_LOGI(TAG, "Initializing EPD for partial refresh (internal)...");
@@ -637,7 +644,7 @@ esp_err_t EInkDisplayHandler::epd_init_partial_internal_(uint32_t transaction_id
 
   // 2. Panel Setting
   std::vector<uint8_t> panel_setting_data = { 0x1F };
-  err = epd_handler_.epd_write_cmd_with_data(0x00, panel_setting_data, transaction_id);
+  err = epd_write_cmd_with_data(0x00, panel_setting_data, transaction_id);
   if (err != ESP_OK) {
     ESP_LOGE(TAG, "Failed to send Panel Setting command: %s", esp_err_to_name(err));
     return err;
@@ -645,37 +652,30 @@ esp_err_t EInkDisplayHandler::epd_init_partial_internal_(uint32_t transaction_id
   vTaskDelay(pdMS_TO_TICKS(MINIMUM_PIN_SETUP_DELAY_MS));
 
   // 3. Power ON
-  err = epd_handler_.epd_write_cmd(0x04, transaction_id);
+  err = epd_write_cmd(0x04, transaction_id);
   if (err != ESP_OK) {
     ESP_LOGE(TAG, "Failed to send Power ON command: %s", esp_err_to_name(err));
     return err;
   }
   vTaskDelay(pdMS_TO_TICKS(MINIMUM_POWER_ON_DELAY_MS));
-  epd_handler_.wait_for_idle();
+  wait_for_idle();
 
   // 4. Partial initialization sequence - Enhanced Display Drive
   std::vector<uint8_t> e0_data = { 0x02 };
-  err = epd_handler_.epd_write_cmd_with_data(0xE0, e0_data, transaction_id);
+  err = epd_write_cmd_with_data(0xE0, e0_data, transaction_id);
   if (err != ESP_OK) {
     ESP_LOGE(TAG, "Failed to send Enhanced Display Drive command (E0): %s", esp_err_to_name(err));
     return err;
   }
 
   std::vector<uint8_t> e5_data = { 0x6E };
-  err = epd_handler_.epd_write_cmd_with_data(0xE5, e5_data, transaction_id);
+  err = epd_write_cmd_with_data(0xE5, e5_data, transaction_id);
   if (err != ESP_OK) {
     ESP_LOGE(TAG, "Failed to send Enhanced Display Drive command (E5): %s", esp_err_to_name(err));
     return err;
   }
 
   is_deep_sleep_ = false;
-
-  err = refresh_old_buffer_(transaction_id);
-  if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to refresh old buffer during partial init: %s", esp_err_to_name(err));
-    return err;
-  }
-
   ESP_LOGI(TAG, "EPD partial init (internal) complete");
   return ESP_OK;
 }
@@ -742,48 +742,201 @@ esp_err_t EInkDisplayHandler::init_touch_() {
   return err;
 }
 
-esp_err_t EInkDisplayHandler::refresh_old_buffer_(uint32_t transaction_id) {
-  ESP_LOGI(TAG, "Refreshing display SRAM to restore state after wake...");
-  esp_err_t err;
 
-  err = epd_handler_.epd_write_cmd(0x92, transaction_id); // enter normal mode
+esp_err_t EInkDisplayHandler::epd_write_cmd(const uint8_t cmd, uint32_t transaction_id) {
+  ESP_LOGI(TAG, "epd_write_cmd: waiting to send 0x%02X", cmd);
+
+  SemaphoreGuard transaction_guard(spi_transaction_mutex_);
+  esp_err_t err =
+    wait_for_transaction_end_(pdMS_TO_TICKS(5000), transaction_id, transaction_guard);
   if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to enter normal mode: %s", esp_err_to_name(err));
+    ESP_LOGE(TAG, "Failed to wait for previous transaction end before sending cmd 0x%02X: %s",
+      cmd, esp_err_to_name(err));
     return err;
   }
 
-  // Write OLD data (0x10) as all 0x00 (white in e-ink terms)
-  // This tells the controller: "assume display was all white"
-  // Matches sample's EPD_WhiteScreen_ALL() which uses 0x00 for old SRAM
-  // The differential refresh: old=0 + new=0 → stay white, old=0 + new=1 → drive to black
-  err = epd_handler_.epd_write_cmd(0x10, transaction_id);
-  if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to send old data command: %s", esp_err_to_name(err));
+  SemaphoreGuard guard(spi_mutex_);
+  if (!guard.take(pdMS_TO_TICKS(5000))) {
+    ESP_LOGE(TAG, "SPI mutex timeout for cmd 0x%02X", cmd);
+    return ESP_ERR_TIMEOUT;
+  }
+  err = dangerous_epd_write_cmd_without_lock_(cmd);
+  ESP_LOGI(TAG, "epd_write_cmd: 0x%02X done", cmd);
   return err;
 }
 
-  // Send the old buffer as old data
-  err = epd_handler_.transfer_spi_data(old_buffer_, DISPLAY_BUFFER_SIZE, transaction_id);
+esp_err_t EInkDisplayHandler::epd_write_data(const uint8_t data, uint32_t transaction_id) {
+  ESP_LOGI(TAG, "epd_write_data: waiting to send 0x%02X", data);
+  SemaphoreGuard transaction_guard(spi_transaction_mutex_);
+  esp_err_t err =
+    wait_for_transaction_end_(pdMS_TO_TICKS(5000), transaction_id, transaction_guard);
   if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to send white baseline to old SRAM: %s", esp_err_to_name(err));
+    ESP_LOGE(TAG, "Failed to wait for previous transaction end before sending data 0x%02X: %s",
+      data, esp_err_to_name(err));
+    return err;
+  }
+  SemaphoreGuard guard(spi_mutex_);
+  if (!guard.take(pdMS_TO_TICKS(5000))) {
+    ESP_LOGE(TAG, "SPI mutex timeout for data 0x%02X", data);
+    return ESP_ERR_TIMEOUT;
+  }
+  err = dangerous_epd_write_data_without_lock_(data);
+  ESP_LOGI(TAG, "epd_write_data: 0x%02X done", data);
   return err;
 }
 
-  // Write NEW data (0x13) with the actual display content
-  // This restores the display to show old_buffer_ content
-  err = epd_handler_.epd_write_cmd(0x13, transaction_id);
+esp_err_t EInkDisplayHandler::epd_write_cmd_with_data(const uint8_t cmd, std::vector<uint8_t>& data, uint32_t transaction_id) {
+  const size_t data_len = data.size();
+  ESP_LOGI(TAG, "epd_write_cmd_with_data: waiting to send cmd 0x%02X with %u bytes of data", cmd, data_len);
+
+  SemaphoreGuard transaction_guard(spi_transaction_mutex_);
+  esp_err_t err =
+    wait_for_transaction_end_(pdMS_TO_TICKS(5000), transaction_id, transaction_guard);
   if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to send new data command: %s", esp_err_to_name(err));
+    ESP_LOGE(TAG, "Failed to wait for previous transaction end before sending cmd 0x%02X: %s, with data",
+      cmd, esp_err_to_name(err));
     return err;
   }
 
-  // Send the last displayed content to new SRAM
-  err = epd_handler_.transfer_spi_data(old_buffer_, DISPLAY_BUFFER_SIZE, transaction_id);
+  SemaphoreGuard guard(spi_mutex_);
+  if (!guard.take(pdMS_TO_TICKS(5000))) {
+    ESP_LOGE(TAG, "SPI mutex timeout for cmd with data 0x%02X", cmd);
+    return ESP_ERR_TIMEOUT;
+  }
+  err = dangerous_epd_write_cmd_without_lock_(cmd);
+  if (err != ESP_OK) {
+    return err;
+  };
+  for (size_t i = 0; i < data_len; ++i) {
+    err = dangerous_epd_write_data_without_lock_(data[i]);
     if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to send display content to new SRAM: %s", esp_err_to_name(err));
       return err;
     }
-
-  ESP_LOGI(TAG, "Display SRAM restored successfully");
+  }
+  ESP_LOGI(TAG, "epd_write_cmd_with_data: cmd 0x%02X with %u bytes of data done", cmd, data_len);
+  return ESP_OK;
+}
+
+
+esp_err_t EInkDisplayHandler::dangerous_epd_write_cmd_without_lock_(const uint8_t cmd) {
+  ESP_LOGI(TAG, "dangerous_epd_write_cmd_without_lock_: sending 0x%02X", cmd);
+  gpio_set_level(PIN_DC, 0); // Command mode
+  spi_transaction_t t {};
+  t.length = 8;t.tx_buffer = &cmd;
+  esp_err_t err = spi_device_polling_transmit(spi_, &t);
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "Failed to send data 0x%02X", cmd);
+  } else {
+    ESP_LOGI(TAG, "dangerous_epd_write_cmd_without_lock_: 0x%02X sent", cmd);
+  }
+  return err;
+}
+
+esp_err_t EInkDisplayHandler::dangerous_epd_write_data_without_lock_(const uint8_t data) {
+  ESP_LOGI(TAG, "dangerous_epd_write_data_without_lock_: sending 0x%02X", data);
+  gpio_set_level(PIN_DC, 1); // Data mode
+  spi_transaction_t t = { };
+  t.length = 8; t.tx_buffer = &data;
+  esp_err_t err = spi_device_polling_transmit(spi_, &t);
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "Failed to send data 0x%02X", data);
+  } else {
+    ESP_LOGI(TAG, "dangerous_epd_write_data_without_lock_: 0x%02X sent", data);
+  }
+  return err;
+}
+
+esp_err_t EInkDisplayHandler::transfer_spi_data(const uint8_t* data, const size_t& length, uint32_t transaction_id) {
+  ESP_LOGI(TAG, "transfer_spi_data: waiting to send %zu bytes of data", length);
+
+  SemaphoreGuard transaction_guard(spi_transaction_mutex_);
+  esp_err_t err =
+    wait_for_transaction_end_(pdMS_TO_TICKS(5000), transaction_id, transaction_guard);
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "Failed to wait for previous transaction end before sending data of %zu bytes: %s",
+      length, esp_err_to_name(err));
+    return err;
+  }
+  SemaphoreGuard guard(spi_mutex_);
+  if (!guard.take(pdMS_TO_TICKS(5000))) {
+    ESP_LOGE(TAG, "SPI mutex timeout for data transfer of %zu bytes", length);
+    return ESP_ERR_TIMEOUT;
+  }
+  ESP_LOGI(TAG, "transfer_spi_data: starting to send %zu bytes of data", length);
+
+  size_t offset = 0;
+  size_t remaining = length;
+  gpio_set_level(PIN_DC, 1); // Data mode
+  while (remaining > 0) {
+    size_t transfer_size = (remaining < DMA_TRANSFER_CHUNK_SIZE) ? remaining : DMA_TRANSFER_CHUNK_SIZE;
+
+    spi_transaction_t t = {};
+    t.length = transfer_size * 8;  // Length in bits
+    t.tx_buffer = data + offset;
+
+    esp_err_t ret = spi_device_polling_transmit(spi_, &t);
+    if (ret != ESP_OK) {
+      ESP_LOGE(TAG, "Failed to send SPI chunk at offset %zu: %s", offset, esp_err_to_name(ret));
+      return ret;
+    }
+
+    remaining -= transfer_size;
+    offset += transfer_size;
+
+    // Yield every 16KB to prevent watchdog timeout
+    if (offset % (16 * 1024) == 0) {
+      ESP_LOGI(TAG, "New data progress: %zu/%zu bytes sent, yielding...", offset, length);
+      vTaskDelay(pdMS_TO_TICKS(1));
+    }
+  }
+
+  ESP_LOGI(TAG, "transfer_spi_data: completed sending %zu bytes of data", length);
+  return ESP_OK;
+}
+
+esp_err_t EInkDisplayHandler::begin_transaction_(TickType_t timeout, uint32_t& out_id) {
+  ESP_LOGI(TAG, "begin_transaction_: waiting to obtain transaction mutex");
+  if (xSemaphoreTake(spi_transaction_mutex_, timeout) != pdTRUE) {
+    ESP_LOGE(TAG, "begin_transaction_: transaction mutex timeout");
+    return ESP_ERR_TIMEOUT;
+  }
+
+  out_id = ++spi_transaction_id;
+  ESP_LOGI(TAG, "begin_transaction_: transaction mutex obtained");
+  return ESP_OK;
+}
+
+esp_err_t EInkDisplayHandler::end_transaction_(void) {
+  ESP_LOGI(TAG, "end_transaction_: releasing transaction mutex");
+  if (xSemaphoreGive(spi_transaction_mutex_) != pdTRUE) {
+    ESP_LOGE(TAG, "end_transaction_: failed to release transaction mutex");
+    return ESP_FAIL;
+  }
+
+  ESP_LOGI(TAG, "end_transaction_: transaction mutex released");
+  return ESP_OK;
+}
+
+esp_err_t EInkDisplayHandler::wait_for_transaction_end_(TickType_t timeout, uint32_t awaiting_transaction_id, SemaphoreGuard& out_transaction_guard) {
+  // Validate transaction ID if provided
+  if (awaiting_transaction_id != 0 && awaiting_transaction_id != spi_transaction_id) {
+    // Invalid transaction ID
+    ESP_LOGE(TAG, "Invalid transaction ID 0x%08X while waiting, current transaction ID: 0x%08X",
+      awaiting_transaction_id, spi_transaction_id);
+    return ESP_ERR_INVALID_ARG;
+  }
+  SemaphoreGuard transaction_guard(spi_transaction_mutex_);
+  if (awaiting_transaction_id == 0) {
+    // wait for current transaction to complete
+    ESP_LOGV(TAG, "Waiting for current transaction 0x%08X to complete",
+      spi_transaction_id);
+    // take the mutex to ensure no transaction is active
+    if (!transaction_guard.take(timeout)) {
+      ESP_LOGE(TAG, "SPI transaction mutex timeout while waiting for transaction end");
+      return ESP_ERR_TIMEOUT;
+    }
+  }
+  // awaited_transaction_id is valid and matches current transaction ID or 0
+  out_transaction_guard = std::move(transaction_guard);
   return ESP_OK;
 }

main/display/eink_display_handler.cpp.old

@@ -0,0 +1,661 @@
+#include "display/eink_display_handler.h"
+#include "display/constants.h"
+#include "common/constants.h"
+#include "esp_log.h"
+#include "esp_heap_caps.h"
+#include "esp_task_wdt.h"
+#include <cstring>
+
+#define TAG "EInkDisplayHandler"
+#define BUSY_ACTIVE_LEVEL   0  // BUSY pin is active low
+#define BUSY_INACTIVE_LEVEL 1
+
+EInkDisplayHandler::EInkDisplayHandler(EventGroupHandle_t system_event_group)
+  : DisplayHandler(system_event_group) {
+  _refresh_mutex = xSemaphoreCreateMutex();
+  if (_refresh_mutex == nullptr) {
+    ESP_LOGE(TAG, "Failed to create refresh mutex");
+  }
+}
+
+EInkDisplayHandler::~EInkDisplayHandler() {
+  if (_refresh_task_handle != nullptr) {
+    vTaskDelete(_refresh_task_handle);
+  }
+  if (_touch_task_handle != nullptr) {
+    vTaskDelete(_touch_task_handle);
+  }
+  if (_refresh_queue != nullptr) {
+    vQueueDelete(_refresh_queue);
+  }
+  if (_lvgl_display != nullptr) {
+    lv_display_delete(_lvgl_display);
+    _lvgl_display = nullptr;
+    if (_lvgl_draw_buf != nullptr) {
+      lv_draw_buf_destroy(_lvgl_draw_buf);
+      _lvgl_draw_buf = nullptr;
+    }
+  }
+  if (_lvgl_touch_indev != nullptr) {
+    lvgl_port_remove_touch(_lvgl_touch_indev);
+  }
+  if (_framebuffer != nullptr) {
+    heap_caps_free(_framebuffer);
+  }
+  if (_refresh_mutex != nullptr) {
+    vSemaphoreDelete(_refresh_mutex);
+  }
+}
+
+void EInkDisplayHandler::init() {
+  ESP_LOGI(TAG, "Initializing E-Ink display handler...");
+
+  // Initialize GPIO pins
+  gpio_config_t io_conf = {};
+  io_conf.pin_bit_mask = (1ULL << PIN_DC) | (1ULL << PIN_RST);
+  io_conf.mode = GPIO_MODE_OUTPUT;
+  io_conf.pull_up_en = GPIO_PULLUP_DISABLE;
+  io_conf.pull_down_en = GPIO_PULLDOWN_DISABLE;
+  io_conf.intr_type = GPIO_INTR_DISABLE;
+  gpio_config(&io_conf);
+
+  // Configure BUSY pin as input (no pull-up like sample code)
+  io_conf.pin_bit_mask = (1ULL << PIN_BUSY);
+  io_conf.mode = GPIO_MODE_INPUT;
+  io_conf.pull_up_en = GPIO_PULLUP_DISABLE;
+  gpio_config(&io_conf);
+
+  // Initialize SPI bus
+  spi_bus_config_t buscfg = {};
+  buscfg.mosi_io_num = 11;  // MOSI pin
+  buscfg.miso_io_num = -1;  // No MISO for e-paper
+  buscfg.sclk_io_num = 12;  // SCK pin
+  buscfg.quadwp_io_num = -1;
+  buscfg.quadhd_io_num = -1;
+  buscfg.max_transfer_sz = DISPLAY_BUFFER_SIZE;
+
+  esp_err_t ret = spi_bus_initialize(SPI2_HOST, &buscfg, SPI_DMA_CH_AUTO);
+  if (ret != ESP_OK) {
+    ESP_LOGE(TAG, "Failed to initialize SPI bus: %s", esp_err_to_name(ret));
+    return;
+  }
+
+  // Add SPI device
+  spi_device_interface_config_t devcfg = {};
+  devcfg.clock_speed_hz = 6 * 1000 * 1000;  // 6 MHz (reduced for reliability)
+  devcfg.mode = 0;  // SPI mode 0
+  devcfg.spics_io_num = PIN_CS;
+  devcfg.queue_size = 7;  // Queue size for non-blocking transactions
+  devcfg.pre_cb = nullptr;
+
+  ret = spi_bus_add_device(SPI2_HOST, &devcfg, &_spi);
+  if (ret != ESP_OK) {
+    ESP_LOGE(TAG, "Failed to add SPI device: %s", esp_err_to_name(ret));
+    return;
+  }
+
+  // Initialize base display and touch devices
+  init_devices(false);  // Don't set ready bit yet
+
+  // Create refresh queue (queue 5 refresh requests)
+  _refresh_queue = xQueueCreate(5, sizeof(bool));
+  if (_refresh_queue == nullptr) {
+    ESP_LOGE(TAG, "Failed to create refresh queue");
+    return;
+  }
+
+  // Create refresh task
+  BaseType_t ret_task = xTaskCreatePinnedToCore(
+    _refresh_task,
+    "eink_refresh",
+    8192,
+    this,
+    5,  // Priority - lower than LVGL task
+    &_refresh_task_handle,
+    1   // Pin to core 1
+  );
+  if (ret_task != pdPASS) {
+    ESP_LOGE(TAG, "Failed to create refresh task");
+    return;
+  }
+
+  // Allocate framebuffer - try PSRAM first, fallback to internal RAM
+  // Note: Internal framebuffer excludes the 8-byte palette (raw pixel data only)
+  const size_t fb_size = DISPLAY_BUFFER_SIZE - 8;  // Exclude palette from internal storage
+  _framebuffer = (uint8_t*)heap_caps_malloc(fb_size, MALLOC_CAP_SPIRAM);
+  if (_framebuffer != nullptr) {
+    _framebuffer_in_psram = true;
+    ESP_LOGI(TAG, "Framebuffer allocated in PSRAM (%zu bytes, LVGL buffer: %d bytes)",
+      fb_size, DISPLAY_BUFFER_SIZE);
+  } else {
+    ESP_LOGW(TAG, "PSRAM not available, allocating framebuffer in internal RAM");
+    _framebuffer = (uint8_t*)heap_caps_malloc(fb_size, MALLOC_CAP_INTERNAL);
+    _framebuffer_in_psram = false;
+    if (_framebuffer == nullptr) {
+      ESP_LOGE(TAG, "Failed to allocate framebuffer");
+      return;
+    }
+    ESP_LOGI(TAG, "Framebuffer allocated in internal RAM (%zu bytes, LVGL buffer: %d bytes)",
+      fb_size, DISPLAY_BUFFER_SIZE);
+  }
+  memset(_framebuffer, 0xFF, fb_size);  // Initialize to white
+
+  // Perform initial full refresh to clear display BEFORE creating LVGL display
+  // This prevents LVGL from trying to render during the initial clear
+  ESP_LOGI(TAG, "Performing initial display clear...");
+  _perform_full_refresh(_framebuffer);
+  ESP_LOGI(TAG, "Initial display clear complete");
+
+  // Create LVGL display manually (no esp_lcd panel for e-paper)
+  lv_display_t* disp = lv_display_create(DISPLAY_WIDTH, DISPLAY_HEIGHT);
+  if (disp == nullptr) {
+    ESP_LOGE(TAG, "Failed to create LVGL display");
+    return;
+  }
+
+  /* 1-bit e-paper display */
+  lv_display_set_color_format(disp, LV_COLOR_FORMAT_I1);
+
+  /* Disable antialiasing for monochrome display to ensure crisp 1px lines */
+  lv_display_set_antialiasing(disp, false);
+
+  /* Create a draw buffer covering ~40 lines */
+  _lvgl_draw_buf = lv_draw_buf_create(DISPLAY_WIDTH, DISPLAY_HEIGHT, LV_COLOR_FORMAT_I1, LV_STRIDE_AUTO);
+  if (_lvgl_draw_buf == nullptr) {
+    ESP_LOGE(TAG, "Failed to create LVGL draw buffer");
+    lv_display_delete(disp);
+    return;
+  }
+
+  lv_display_set_draw_buffers(disp, _lvgl_draw_buf, NULL);
+  lv_display_set_render_mode(disp, LV_DISPLAY_RENDER_MODE_DIRECT);
+
+  // Set custom flush callback and user data
+  lv_display_set_flush_cb(disp, _lvgl_flush_cb);
+  lv_display_set_user_data(disp, this);
+
+  _lvgl_display = disp;
+
+  ESP_LOGI(TAG, "LVGL display registered");
+
+  // Register GT911 touch input with LVGL, only if touch handle is valid
+  esp_lcd_touch_handle_t tp_handle = get_touch_handle();
+  if (tp_handle == nullptr) {
+    ESP_LOGE(TAG, "Touch handle is NULL — touch initialization failed; skipping LVGL touch registration");
+  } else {
+    const lvgl_port_touch_cfg_t touch_cfg = {
+      .disp = _lvgl_display,
+      .handle = tp_handle,
+      .scale = {}, // Default scaling
+    };
+
+    _lvgl_touch_indev = lvgl_port_add_touch(&touch_cfg);
+    if (_lvgl_touch_indev == nullptr) {
+      ESP_LOGE(TAG, "Failed to register LVGL touch input");
+      return;
+    }
+
+    // Override touch read callback to check BUSY pin
+    lv_indev_set_read_cb(_lvgl_touch_indev, _lvgl_touch_read_cb);
+    lv_indev_set_user_data(_lvgl_touch_indev, this);
+
+    ESP_LOGI(TAG, "LVGL touch input registered");
+  }
+
+  // Set display ready bits
+  xEventGroupSetBits(_system_event_group, DISPLAY_READY_BIT | TOUCH_CALIBRATED_BIT);
+  ESP_LOGI(TAG, "E-Ink display handler initialized successfully");
+}
+
+void EInkDisplayHandler::start_touch_task() {
+  // Note: With lvgl_port_add_touch, the ESP-IDF LVGL port handles touch reading internally
+  // We don't need a separate touch task unless we want custom processing
+  ESP_LOGI(TAG, "Touch input handled by LVGL port");
+}
+
+void EInkDisplayHandler::request_full_refresh() {
+  if (xSemaphoreTake(_refresh_mutex, pdMS_TO_TICKS(100)) == pdTRUE) {
+    _force_full_refresh = true;
+    _partial_refresh_count = 0;
+    xSemaphoreGive(_refresh_mutex);
+    ESP_LOGI(TAG, "Full refresh requested");
+  }
+}
+
+bool EInkDisplayHandler::is_busy() const {
+  return gpio_get_level(PIN_BUSY) == BUSY_ACTIVE_LEVEL;  // BUSY is active LOW
+}
+
+void EInkDisplayHandler::_lvgl_flush_cb(lv_display_t* disp, const lv_area_t* area, uint8_t* px_map) {
+  EInkDisplayHandler* handler = static_cast<EInkDisplayHandler*>(lv_display_get_user_data(disp));
+  if (handler == nullptr) {
+    ESP_LOGE(TAG, "Invalid handler in flush callback");
+    lv_display_flush_ready(disp);
+    return;
+  }
+
+  // Check if display is busy with detailed logging
+  int busy_level = gpio_get_level(PIN_BUSY);
+  ESP_LOGI(TAG, "Flush callback: BUSY pin = %d, is_busy() = %d", busy_level, handler->is_busy());
+
+  if (handler->is_busy()) {
+    ESP_LOGW(TAG, "Display busy (BUSY pin = 0), skipping flush");
+    lv_display_flush_ready(disp);
+    return;
+  }
+
+  // Wait for any ongoing refresh to complete
+  handler->_wait_for_busy();
+
+  bool perform_full_refresh = false;
+
+  if (xSemaphoreTake(handler->_refresh_mutex, pdMS_TO_TICKS(100)) == pdTRUE) {
+    // Check if full refresh is needed
+    if (handler->_force_full_refresh) {
+      perform_full_refresh = true;
+      handler->_force_full_refresh = false;
+      handler->_partial_refresh_count = 0;
+    } else {
+      handler->_partial_refresh_count++;
+      if (handler->_partial_refresh_count >= PARTIAL_REFRESH_THRESHOLD) {
+        perform_full_refresh = true;
+        handler->_partial_refresh_count = 0;
+      }
+    }
+    xSemaphoreGive(handler->_refresh_mutex);
+  }
+
+  // Copy LVGL buffer to framebuffer
+  // For 1-bit mode, LVGL provides data in packed format (8 pixels per byte)
+  // CRITICAL: Skip first 8 bytes (LVGL I1 palette) as per LVGL documentation
+  uint8_t* pixel_data = px_map + 8;  // Skip 8-byte palette
+  int32_t w = lv_area_get_width(area);
+  int32_t h = lv_area_get_height(area);
+
+  ESP_LOGI(TAG, "Flushing area: x=%d, y=%d, w=%d, h=%d, full_refresh=%d",
+    area->x1, area->y1, w, h, perform_full_refresh);
+  ESP_LOGI(TAG, "Buffer: px_map=%p, pixel_data=%p, palette skipped: %d bytes",
+    (void*)px_map, (void*)pixel_data, 8);
+
+  // Check if this is a full screen update - if so, simple copy
+  if (area->x1 == 0 && area->y1 == 0 && w == DISPLAY_WIDTH && h == DISPLAY_HEIGHT) {
+    ESP_LOGI(TAG, "Full screen update, direct copy (skipping palette)");
+    memcpy(handler->_framebuffer, pixel_data, DISPLAY_BUFFER_SIZE - 8);
+  } else {
+    ESP_LOGI(TAG, "Partial area update");
+    // In DIRECT render mode, px_map points to the full screen buffer
+    // The stride is always the full display width
+    const uint32_t stride = DISPLAY_WIDTH / 8;  // 800 / 8 = 100 bytes per row
+
+    // Check if we can do row-by-row copy (byte-aligned on both x1 and width)
+    bool byte_aligned = (area->x1 % 8 == 0) && (w % 8 == 0);
+
+    if (byte_aligned) {
+      // Optimized: byte-aligned row copy
+      ESP_LOGI(TAG, "Byte-aligned copy: x=%ld, y=%ld, w=%ld, h=%ld",
+        (long)area->x1, (long)area->y1, (long)w, (long)h);
+
+      uint32_t x_byte = area->x1 / 8;
+      uint32_t width_bytes = w / 8;
+
+      for (int32_t y = 0; y < h; y++) {
+        int32_t fb_y = area->y1 + y;
+        if (fb_y >= DISPLAY_HEIGHT) break;
+
+        uint8_t* src = pixel_data + (fb_y * stride + x_byte);
+        uint8_t* dst = handler->_framebuffer + (fb_y * stride + x_byte);
+        memcpy(dst, src, width_bytes);
+      }
+    } else {
+      // Bit-level copy for non-aligned regions
+      ESP_LOGI(TAG, "Bit-level copy: x=%ld, y=%ld, w=%ld, h=%ld",
+        (long)area->x1, (long)area->y1, (long)w, (long)h);
+
+      for (int32_t y = 0; y < h; y++) {
+        int32_t fb_y = area->y1 + y;
+        if (fb_y >= DISPLAY_HEIGHT) break;
+
+        for (int32_t x = 0; x < w; x++) {
+          int32_t fb_x = area->x1 + x;
+          if (fb_x >= DISPLAY_WIDTH) break;
+
+          // Get pixel from source buffer (using full screen coordinates)
+          size_t src_byte_idx = fb_y * stride + (fb_x / 8);
+          size_t src_bit_idx = fb_x % 8;
+          uint8_t src_bit = (pixel_data[src_byte_idx] >> (7 - src_bit_idx)) & 0x01;
+
+          // Set pixel in destination buffer
+          size_t dst_byte_idx = fb_y * stride + (fb_x / 8);
+          size_t dst_bit_idx = fb_x % 8;
+
+          if (dst_byte_idx < (DISPLAY_BUFFER_SIZE - 8)) {
+            if (src_bit) {
+              handler->_framebuffer[dst_byte_idx] |= (1 << (7 - dst_bit_idx));
+            } else {
+              handler->_framebuffer[dst_byte_idx] &= ~(1 << (7 - dst_bit_idx));
+            }
+          }
+        }
+      }
+    }
+  }
+
+  // Queue refresh request (non-blocking)
+  if (handler->_refresh_queue != nullptr) {
+    if (xQueueSend(handler->_refresh_queue, &perform_full_refresh, 0) != pdPASS) {
+      ESP_LOGW(TAG, "Refresh queue full, skipping refresh");
+    } else {
+      ESP_LOGI(TAG, "Queued %s refresh", perform_full_refresh ? "full" : "partial");
+    }
+  }
+
+  lv_display_flush_ready(disp);
+}
+
+void EInkDisplayHandler::_lvgl_touch_read_cb(lv_indev_t* indev, lv_indev_data_t* data) {
+  EInkDisplayHandler* handler = static_cast<EInkDisplayHandler*>(lv_indev_get_user_data(indev));
+
+  // Disable touch input during display refresh (BUSY)
+  if (handler->is_busy()) {
+    data->state = LV_INDEV_STATE_RELEASED;
+    data->continue_reading = false;
+    return;
+  }
+
+  esp_lcd_touch_handle_t tp_handle = handler->get_touch_handle();
+  if (tp_handle == nullptr) {
+    data->state = LV_INDEV_STATE_RELEASED;
+    return;
+  }
+
+
+  // Read touch data from GT911
+  esp_err_t ret = esp_lcd_touch_read_data(tp_handle);
+  if (ret == ESP_OK) {
+    uint8_t touch_cnt = 0;
+    // Get touch data using new API
+    esp_lcd_touch_point_data_t point_data[1];
+    esp_lcd_touch_get_data(tp_handle, point_data, &touch_cnt, 1);
+
+    if (touch_cnt > 0) {
+      ESP_LOGI(TAG, "Touch data read successfully: x=%d, y=%d", point_data[0].x, point_data[0].y);
+      data->point.x = point_data[0].x;
+      data->point.y = point_data[0].y;
+      data->state = LV_INDEV_STATE_PRESSED;
+    } else {
+      data->state = LV_INDEV_STATE_RELEASED;
+    }
+  } else {
+    data->state = LV_INDEV_STATE_RELEASED;
+  }
+
+  data->continue_reading = false;
+}
+
+void EInkDisplayHandler::_perform_full_refresh(const uint8_t* framebuffer) {
+  ESP_LOGI(TAG, "Starting full refresh (3 seconds)...");
+
+  _wait_for_busy();
+
+  // Step 1: Write old data (0x10) - Arduino uses 0xFF (all white) for base map
+  epd_write_cmd(0x10);
+
+  if (xSemaphoreTake(_spi_mutex, pdMS_TO_TICKS(5000)) != pdTRUE) {
+    ESP_LOGE(TAG, "SPI mutex timeout in full refresh step 1");
+    return;
+  }
+  gpio_set_level(PIN_DC, 1);  // Data mode
+
+  ESP_LOGI(TAG, "Starting SPI data transmission for old data (0x10)...");
+
+  // Send 0xFF (white) for all old data, matching Arduino EPD_SetRAMValue_BaseMap
+  // Use DMA transfers in chunks for better performance
+  static uint8_t white_buffer[4096];  // 4KB chunk buffer
+  memset(white_buffer, 0xFF, sizeof(white_buffer));
+
+  const size_t CHUNK_SIZE = sizeof(white_buffer);
+  size_t remaining = DISPLAY_BUFFER_SIZE - 8;  // Exclude palette from transmission
+  size_t offset = 0;
+
+  while (remaining > 0) {
+    size_t transfer_size = (remaining < CHUNK_SIZE) ? remaining : CHUNK_SIZE;
+
+    spi_transaction_t t = {};
+    t.length = transfer_size * 8;  // Length in bits
+    t.tx_buffer = white_buffer;
+
+    esp_err_t ret = spi_device_polling_transmit(_spi, &t);
+    if (ret != ESP_OK) {
+      ESP_LOGE(TAG, "Failed to send SPI chunk at offset %zu: %s", offset, esp_err_to_name(ret));
+      break;
+    }
+
+    remaining -= transfer_size;
+    offset += transfer_size;
+
+    // Yield every 16KB to prevent watchdog timeout
+    if (offset % (16 * 1024) == 0) {
+      ESP_LOGI(TAG, "Old data progress: %zu/%zu bytes (%.1f%%)", offset, remaining,
+        (float)offset * 100.0f / (float)remaining);
+      vTaskDelay(pdMS_TO_TICKS(1));
+    }
+  }
+  ESP_LOGI(TAG, "Completed SPI data transmission for old data");
+  xSemaphoreGive(_spi_mutex);
+
+  // Step 2: Write new data (0x13)
+  epd_write_cmd(0x13);
+
+  if (xSemaphoreTake(_spi_mutex, pdMS_TO_TICKS(5000)) != pdTRUE) {
+    ESP_LOGE(TAG, "SPI mutex timeout in full refresh step 2");
+    return;
+  }
+  gpio_set_level(PIN_DC, 1);  // Data mode
+
+  ESP_LOGI(TAG, "Starting SPI data transmission for new data (0x13)...");
+
+  // Send actual framebuffer data in chunks using DMA for better performance
+  offset = 0;
+  remaining = DISPLAY_BUFFER_SIZE - 8;  // Reset remaining for step 2
+
+  while (remaining > 0) {
+    size_t transfer_size = (remaining < CHUNK_SIZE) ? remaining : CHUNK_SIZE;
+
+    spi_transaction_t t = {};
+    t.length = transfer_size * 8;  // Length in bits
+    t.tx_buffer = framebuffer + offset;
+
+    esp_err_t ret = spi_device_polling_transmit(_spi, &t);
+    if (ret != ESP_OK) {
+      ESP_LOGE(TAG, "Failed to send SPI chunk at offset %zu: %s", offset, esp_err_to_name(ret));
+      break;
+    }
+
+    remaining -= transfer_size;
+    offset += transfer_size;
+
+    // Yield every 16KB to prevent watchdog timeout
+    if (offset % (16 * 1024) == 0) {
+      ESP_LOGI(TAG, "New data progress: %zu/%zu bytes (%.1f%%)", offset, remaining,
+        (float)offset * 100.0f / (float)remaining);
+      vTaskDelay(pdMS_TO_TICKS(1));
+    }
+  }
+
+  ESP_LOGI(TAG, "Completed SPI data transmission for new data");
+  xSemaphoreGive(_spi_mutex);
+
+  // Step 3: Trigger display refresh (DRF)
+  epd_write_cmd(0x12);
+  // Critical delay - sample code says "!!!The delay here is necessary, 200uS at least!!!"
+  vTaskDelay(pdMS_TO_TICKS(10));
+  ESP_LOGI(TAG, "Display refresh triggered, BUSY pin: %d", gpio_get_level(PIN_BUSY));
+
+  // Wait for refresh to complete
+  _wait_for_busy();
+
+  ESP_LOGI(TAG, "Full refresh complete");
+}
+
+void EInkDisplayHandler::_perform_partial_refresh(const uint8_t* framebuffer) {
+  ESP_LOGI(TAG, "Starting partial refresh (0.3 seconds)...");
+
+  _wait_for_busy();
+
+  // Step 1: Configure VCOM for partial refresh
+  const uint8_t vcom_data[] = { 0xA9, 0x07 };
+  epd_write_cmd_with_data(0x50, vcom_data, 2);
+
+  // Step 2: Enter partial refresh mode
+  epd_write_cmd(0x91);
+
+  // Step 3: Define partial window (full screen for now)
+  // Format: 0x90 + 9 bytes (x_start_H, x_start_L, x_end_H, x_end_L, y_start_H, y_start_L, y_end_H, y_end_L, 0x01)
+  // For full screen: x=0 to 799 (0x031F), y=0 to 479 (0x01DF)
+  const uint8_t window_data[] = {
+    0x00, 0x00,  // x_start = 0
+    0x03, 0x1F,  // x_end = 799 (0x31F)
+    0x00, 0x00,  // y_start = 0
+    0x01, 0xDF,  // y_end = 479 (0x1DF)
+    0x01         // PT_SCAN
+  };
+  epd_write_cmd_with_data(0x90, window_data, 9);
+
+  // Step 4: Write new data (0x13 command)
+  epd_write_cmd(0x13);
+
+  if (xSemaphoreTake(_spi_mutex, pdMS_TO_TICKS(5000)) != pdTRUE) {
+    ESP_LOGE(TAG, "SPI mutex timeout in partial refresh");
+    return;
+  }
+  gpio_set_level(PIN_DC, 1);  // Data mode
+
+  ESP_LOGI(TAG, "Starting SPI data transmission for partial refresh...");
+
+  // Send framebuffer data in chunks using DMA for better performance
+  const size_t CHUNK_SIZE = 4096;  // 4KB chunks
+  size_t remaining = DISPLAY_BUFFER_SIZE - 8;  // Exclude palette from transmission
+  size_t offset = 0;
+
+  while (remaining > 0) {
+    size_t transfer_size = (remaining < CHUNK_SIZE) ? remaining : CHUNK_SIZE;
+
+    spi_transaction_t t = {};
+    t.length = transfer_size * 8;  // Length in bits
+    t.tx_buffer = framebuffer + offset;
+
+    esp_err_t ret = spi_device_polling_transmit(_spi, &t);
+    if (ret != ESP_OK) {
+      ESP_LOGE(TAG, "Failed to send SPI chunk at offset %zu: %s", offset, esp_err_to_name(ret));
+      break;
+    }
+
+    remaining -= transfer_size;
+    offset += transfer_size;
+
+    // Yield every 16KB to prevent watchdog timeout
+    if (offset % (16 * 1024) == 0) {
+      ESP_LOGI(TAG, "Partial refresh progress: %zu/%zu bytes (%.1f%%)", offset, remaining,
+        (float)offset * 100.0f / (float)remaining);
+      vTaskDelay(pdMS_TO_TICKS(1));
+    }
+  }
+  ESP_LOGI(TAG, "Completed SPI data transmission for partial refresh");
+  xSemaphoreGive(_spi_mutex);
+
+  // Step 5: Trigger partial display refresh (DRF)
+  epd_write_cmd(0x12);
+  // Critical delay - sample code says "!!!The delay here is necessary, 200uS at least!!!"
+  vTaskDelay(pdMS_TO_TICKS(10));
+  ESP_LOGI(TAG, "Partial refresh triggered, BUSY pin: %d", gpio_get_level(PIN_BUSY));
+
+  // Wait for refresh to complete
+  _wait_for_busy();
+
+  // Step 6: Exit partial refresh mode
+  epd_write_cmd(0x92);
+
+  ESP_LOGI(TAG, "Partial refresh complete");
+}
+
+void EInkDisplayHandler::_refresh_task(void* param) {
+  EInkDisplayHandler* handler = static_cast<EInkDisplayHandler*>(param);
+  bool perform_full_refresh = false;
+
+  ESP_LOGI(TAG, "Refresh task started");
+
+  while (true) {
+    // Wait for refresh request
+    if (xQueueReceive(handler->_refresh_queue, &perform_full_refresh, portMAX_DELAY) == pdTRUE) {
+      // Perform the requested refresh type
+      if (perform_full_refresh) {
+        ESP_LOGI(TAG, "Refresh task: Performing full refresh...");
+        handler->_perform_full_refresh(handler->_framebuffer);
+      } else {
+        ESP_LOGI(TAG, "Refresh task: Performing partial refresh...");
+        handler->_perform_partial_refresh(handler->_framebuffer);
+      }
+    }
+  }
+}
+
+void EInkDisplayHandler::_wait_for_busy() {
+  ESP_LOGI(TAG, "Waiting for display ready (BUSY pin)...");
+  int initial_level = gpio_get_level(PIN_BUSY);
+  ESP_LOGI(TAG, "Initial BUSY pin level: %d (0=BUSY, 1=FREE)", initial_level);
+
+  // If already free, no need to wait
+  if (initial_level == BUSY_INACTIVE_LEVEL) {
+    ESP_LOGI(TAG, "Display already ready (BUSY pin = 1)");
+    return;
+  }
+
+  int timeout = 0;
+  while (gpio_get_level(PIN_BUSY) == BUSY_ACTIVE_LEVEL) {  // 0=BUSY, 1=FREE
+    vTaskDelay(pdMS_TO_TICKS(100));
+    timeout++;
+    if (timeout > 100) {  // 10 second timeout
+      ESP_LOGE(TAG, "Display BUSY timeout! Pin level: %d", gpio_get_level(PIN_BUSY));
+      ESP_LOGW(TAG, "Attempting hardware reset...");
+
+      // Hardware reset sequence
+      gpio_set_level(PIN_RST, 0);
+      vTaskDelay(pdMS_TO_TICKS(10));
+      gpio_set_level(PIN_RST, 1);
+      vTaskDelay(pdMS_TO_TICKS(100));
+
+      // Re-initialize display
+      ESP_LOGI(TAG, "Re-initializing display after reset...");
+      _epd_init();
+
+      // Check if reset worked
+      int reset_timeout = 0;
+      while (gpio_get_level(PIN_BUSY) == BUSY_ACTIVE_LEVEL) {
+        vTaskDelay(pdMS_TO_TICKS(100));
+        reset_timeout++;
+        if (reset_timeout > 50) {  // 5 second timeout after reset
+          ESP_LOGE(TAG, "Display reset failed! Still busy after reset.");
+          break;
+        }
+      }
+
+      if (gpio_get_level(PIN_BUSY) != BUSY_ACTIVE_LEVEL) {
+        ESP_LOGI(TAG, "Display reset successful after %d tenths of a second", reset_timeout);
+      }
+      break;
+    }
+
+    // Log every 2 seconds to track progress
+    if (timeout % 20 == 0) {
+      ESP_LOGW(TAG, "Still waiting for BUSY pin, timeout: %d/100, level: %d",
+        timeout, gpio_get_level(PIN_BUSY));
+    }
+  }
+  ESP_LOGI(TAG, "Display ready after %d tenths of a second", timeout);
+}
+
+void EInkDisplayHandler::_convert_buffer_to_epaper(const uint8_t* lvgl_buf, uint8_t* epd_buf, size_t size) {
+  // LVGL 1-bit format is already compatible with e-paper
+  // Just copy directly
+  memcpy(epd_buf, lvgl_buf, size);
+}

main/display/eink_display_handler.h

@@ -5,9 +5,9 @@
 #include "common/semaphore_guard.h"
 #include <vector>
 #include <atomic>
-#include "epd_handler.h"
 
 // Refresh mode configuration
+#define PARTIAL_REFRESH_THRESHOLD 10  // Full refresh every N partial refreshes
 #define DISPLAY_WIDTH 800
 #define DISPLAY_HEIGHT 480
 
@@ -56,43 +56,71 @@ public:
 
   esp_err_t refresh_display(void);
   esp_err_t full_write(const uint8_t* framebuffer, const bool white_basemap = true);
-  esp_err_t partial_refresh(const uint8_t* framebuffer, const RefreshArea& area, const bool is_last_partial_update = true);
+  esp_err_t partial_refresh(const uint8_t* framebuffer, const RefreshArea& area);
   esp_err_t clear_display(void);
   esp_err_t deep_sleep_display(void);
   // Request a full refresh on next flush
   void request_full_refresh(void);
 
-  bool is_busy() {
-    return epd_handler_.is_busy();
-  }
+  // Check if display is busy (refreshing)
+  bool is_busy(void) const;
+  void wait_for_idle(void) const;
 
   esp_lcd_touch_handle_t get_touch_handle() const { return tp_handle_; }
 
+protected:
+  esp_err_t epd_write_cmd(const uint8_t cmd, uint32_t transaction_id);
+  esp_err_t epd_write_data(const uint8_t data, uint32_t transaction_id);
+  esp_err_t epd_write_cmd_with_data(const uint8_t cmd, std::vector<uint8_t>& data, uint32_t transaction_id);
+  esp_err_t transfer_spi_data(const uint8_t* data, const size_t& length, uint32_t transaction_id);
+
 private:
 
   esp_err_t init_display_pins_(void);
-  esp_err_t epd_init_internal_(uint32_t transaction_id); // full fast refresh init
+  esp_err_t epd_init_(void); // full fast refresh init
+  esp_err_t epd_init_partial_(void); // partial refresh init (standalone)
   esp_err_t epd_init_partial_internal_(uint32_t transaction_id); // partial refresh init (within existing transaction)
   esp_err_t init_touch_(void);
+  esp_err_t dangerous_epd_write_cmd_without_lock_(const uint8_t cmd);
+  esp_err_t dangerous_epd_write_data_without_lock_(const uint8_t data);
 
-  // write to the internal draw buffer
-  void write_to_buffer_(const uint8_t* src, const RefreshArea& area);
-  // write the internal draw buffer to the display's old sram
-  esp_err_t refresh_old_buffer_(uint32_t transaction_id);
+  esp_err_t begin_transaction_(TickType_t timeout, uint32_t& out_id);
+  esp_err_t end_transaction_(void);
+  // given a transaction ID, wait for current transaction to complete. The transaction ID will determine if the wait is needed.
+  esp_err_t wait_for_transaction_end_(TickType_t timeout, uint32_t awaiting_transaction_id, SemaphoreGuard& out_transaction_guard);
 
+  friend class TransactionGuard;
 
-  EPDHandler epd_handler_;
   uint32_t partial_refresh_count_ = 0;
   bool force_full_refresh_ = false;
   std::atomic<bool> is_deep_sleep_ { false };
 
+  SemaphoreHandle_t spi_mutex_ = nullptr;
+  SemaphoreHandle_t spi_transaction_mutex_ = nullptr;
   SemaphoreHandle_t refresh_mutex_ = nullptr;
+  uint32_t spi_transaction_id = 0; // For tracking SPI transactions
+  spi_device_handle_t spi_ = nullptr;
   esp_lcd_panel_io_handle_t tp_io_handle_ = nullptr;
   esp_lcd_touch_handle_t tp_handle_ = nullptr;
-
-  // this buffer reflects the current display state (1=black, 0=white)
-  uint8_t* draw_buffer_ = nullptr;
-  uint8_t* old_buffer_ = nullptr;
-  RefreshArea refresh_area_ = { 0, 0, 0, 0 };
 };
 
+
+class TransactionGuard {
+public:
+  TransactionGuard(EInkDisplayHandler& handler, TickType_t timeout = portMAX_DELAY)
+    : handler_(handler) { }
+  ~TransactionGuard() { if (transaction_id_) handler_.end_transaction_(); }
+
+  esp_err_t begin(TickType_t timeout = portMAX_DELAY) {
+    esp_err_t err = handler_.begin_transaction_(timeout, transaction_id_);
+    return err;
+  }
+  uint32_t transaction_id() const { return transaction_id_; }
+  bool is_active() const { return transaction_id_ != 0; }
+private:
+  // delete copy constructor and assignment operator
+  TransactionGuard(const TransactionGuard&) = delete;
+  TransactionGuard& operator=(const TransactionGuard&) = delete;
+  EInkDisplayHandler& handler_;
+  uint32_t transaction_id_ = 0;
+};

main/display/eink_display_handler.h.old

@@ -0,0 +1,66 @@
+#pragma once
+#include "display/display.h"
+#include "lvgl.h"
+#include "esp_lvgl_port.h"
+#include "freertos/semphr.h"
+
+// Refresh mode configuration
+#define PARTIAL_REFRESH_THRESHOLD 10  // Full refresh every N partial refreshes
+#define DISPLAY_WIDTH 800
+#define DISPLAY_HEIGHT 480
+#define DISPLAY_BUFFER_SIZE (((DISPLAY_WIDTH * DISPLAY_HEIGHT) / 8) + 8)  // 1-bit per pixel + 8-byte palette
+
+class EInkDisplayHandler : public DisplayHandler {
+public:
+  EInkDisplayHandler(EventGroupHandle_t system_event_group);
+  virtual ~EInkDisplayHandler();
+
+  void init();
+  void start_touch_task();
+
+  // Request a full refresh on next flush
+  void request_full_refresh();
+
+  // Check if display is busy (refreshing)
+  bool is_busy() const;
+
+private:
+  // LVGL display and input device handles
+  lv_display_t* _lvgl_display = nullptr;
+  lv_indev_t* _lvgl_touch_indev = nullptr;
+  lv_draw_buf_t* _lvgl_draw_buf = nullptr;
+
+  // Framebuffer
+  uint8_t* _framebuffer = nullptr;
+  bool _framebuffer_in_psram = false;
+
+  // Refresh tracking
+  uint32_t _partial_refresh_count = 0;
+  bool _force_full_refresh = false;
+  SemaphoreHandle_t _refresh_mutex = nullptr;
+
+  // Touch task
+  TaskHandle_t _touch_task_handle = nullptr;
+
+  // Refresh task and queue
+  TaskHandle_t _refresh_task_handle = nullptr;
+  QueueHandle_t _refresh_queue = nullptr;
+
+  // LVGL callbacks
+  static void _lvgl_flush_cb(lv_display_t* disp, const lv_area_t* area, uint8_t* px_map);
+  static void _lvgl_touch_read_cb(lv_indev_t* indev, lv_indev_data_t* data);
+
+  // Display operations
+  void _perform_full_refresh(const uint8_t* framebuffer);
+  void _perform_partial_refresh(const uint8_t* framebuffer);
+  void _wait_for_busy();
+
+  // Touch task
+  static void _touch_task(void* param);
+
+  // Refresh task
+  static void _refresh_task(void* param);
+
+  // Helper to convert LVGL 1-bit buffer to e-paper format
+  void _convert_buffer_to_epaper(const uint8_t* lvgl_buf, uint8_t* epd_buf, size_t size);
+};

main/display/epd_handler.cpp

@@ -1,326 +0,0 @@
-#include "display/epd_handler.h"
-#include "esp_log.h"
-#include "display/constants.h"
-#include "common/constants.h"
-#include "esp_lcd_touch_gt911.h"
-#include <driver/i2c.h>
-#define TAG "EPDHandler"
-
-#define BUSY_ACTIVE_LEVEL   0  // BUSY pin is active low
-#define BUSY_INACTIVE_LEVEL 1
-#define DMA_TRANSFER_CHUNK_SIZE 4096  // 4KB chunk size for DMA transfers
-
-EPDHandler::EPDHandler() {
-  spi_mutex_ = xSemaphoreCreateMutex();
-  if (spi_mutex_ == nullptr) {
-    ESP_LOGE(TAG, "Failed to create SPI mutex");
-  }
-  spi_transaction_mutex_ = xSemaphoreCreateMutex();
-  if (spi_transaction_mutex_ == nullptr) {
-    ESP_LOGE(TAG, "Failed to create SPI transaction mutex");
-  }
-}
-
-EPDHandler::~EPDHandler() {
-  if (spi_mutex_ != nullptr) {
-    vSemaphoreDelete(spi_mutex_);
-  }
-  if (spi_transaction_mutex_ != nullptr) {
-    vSemaphoreDelete(spi_transaction_mutex_);
-  }
-  if (spi_ != nullptr) {
-    spi_bus_remove_device(spi_);
-  }
-}
-
-esp_err_t EPDHandler::init() {
-  esp_err_t err;
-
-  // Initialize SPI bus
-  spi_bus_config_t buscfg = {};
-  buscfg.mosi_io_num = 11;  // MOSI pin
-  buscfg.miso_io_num = -1;  // No MISO for e-paper
-  buscfg.sclk_io_num = 12;  // SCK pin
-  buscfg.quadwp_io_num = -1;
-  buscfg.quadhd_io_num = -1;
-  buscfg.max_transfer_sz = DMA_TRANSFER_CHUNK_SIZE;
-
-  err = spi_bus_initialize(SPI2_HOST, &buscfg, SPI_DMA_CH_AUTO);
-  if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to initialize SPI bus: %s", esp_err_to_name(err));
-    return err;
-  }
-
-  // Add SPI device
-  spi_device_interface_config_t devcfg = {};
-  devcfg.clock_speed_hz = 10 * 1000 * 1000;  // 10 MHz
-  devcfg.mode = 0;  // SPI mode 0
-  devcfg.spics_io_num = PIN_CS;
-  devcfg.queue_size = 7;  // Queue size for non-blocking transactions
-  devcfg.pre_cb = nullptr;
-
-  err = spi_bus_add_device(SPI2_HOST, &devcfg, &spi_);
-  if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to add SPI device: %s", esp_err_to_name(err));
-    return err;
-  }
-
-  return ESP_OK;
-}
-
-// Check if display is busy (refreshing)
-bool EPDHandler::is_busy(void) const {
-  return gpio_get_level(PIN_BUSY) != BUSY_ACTIVE_LEVEL;  // BUSY is active LOW
-}
-void EPDHandler::wait_for_idle(void) const {
-  ESP_LOGI(TAG, "Waiting for display ready (BUSY pin)...");
-  int initial_level = gpio_get_level(PIN_BUSY);
-  ESP_LOGI(TAG, "Initial BUSY pin level: %d (0=BUSY, 1=FREE)", initial_level);
-
-  // If already free, no need to wait
-  if (initial_level == BUSY_INACTIVE_LEVEL) {
-    ESP_LOGI(TAG, "Display already ready (BUSY pin = 1)");
-    return;
-  }
-  while (gpio_get_level(PIN_BUSY) != BUSY_INACTIVE_LEVEL) {
-    vTaskDelay(pdMS_TO_TICKS(10));
-  }
-  ESP_LOGI(TAG, "Display is now ready (BUSY pin = 1)");
-}
-
-esp_err_t EPDHandler::epd_write_cmd(const uint8_t cmd, uint32_t transaction_id) {
-  ESP_LOGI(TAG, "epd_write_cmd: waiting to send 0x%02X", cmd);
-
-  SemaphoreGuard transaction_guard(spi_transaction_mutex_);
-  esp_err_t err =
-    wait_for_transaction_end_(pdMS_TO_TICKS(5000), transaction_id, transaction_guard);
-  if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to wait for previous transaction end before sending cmd 0x%02X: %s",
-      cmd, esp_err_to_name(err));
-    return err;
-  }
-
-  SemaphoreGuard guard(spi_mutex_);
-  if (!guard.take(pdMS_TO_TICKS(5000))) {
-    ESP_LOGE(TAG, "SPI mutex timeout for cmd 0x%02X", cmd);
-    return ESP_ERR_TIMEOUT;
-  }
-  err = dangerous_epd_write_cmd_without_lock_(cmd);
-  ESP_LOGI(TAG, "epd_write_cmd: 0x%02X done", cmd);
-  return err;
-}
-
-esp_err_t EPDHandler::epd_write_data(const uint8_t data, uint32_t transaction_id) {
-  ESP_LOGI(TAG, "epd_write_data: waiting to send 0x%02X", data);
-  SemaphoreGuard transaction_guard(spi_transaction_mutex_);
-  esp_err_t err =
-    wait_for_transaction_end_(pdMS_TO_TICKS(5000), transaction_id, transaction_guard);
-  if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to wait for previous transaction end before sending data 0x%02X: %s",
-      data, esp_err_to_name(err));
-    return err;
-  }
-  SemaphoreGuard guard(spi_mutex_);
-  if (!guard.take(pdMS_TO_TICKS(5000))) {
-    ESP_LOGE(TAG, "SPI mutex timeout for data 0x%02X", data);
-    return ESP_ERR_TIMEOUT;
-  }
-  err = dangerous_epd_write_data_without_lock_(data);
-  ESP_LOGI(TAG, "epd_write_data: 0x%02X done", data);
-  return err;
-}
-
-esp_err_t EPDHandler::epd_write_cmd_with_data(const uint8_t cmd, std::vector<uint8_t>& data, uint32_t transaction_id) {
-  const size_t data_len = data.size();
-  ESP_LOGI(TAG, "epd_write_cmd_with_data: waiting to send cmd 0x%02X with %u bytes of data", cmd, data_len);
-
-  SemaphoreGuard transaction_guard(spi_transaction_mutex_);
-  esp_err_t err =
-    wait_for_transaction_end_(pdMS_TO_TICKS(5000), transaction_id, transaction_guard);
-  if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to wait for previous transaction end before sending cmd 0x%02X: %s, with data",
-      cmd, esp_err_to_name(err));
-    return err;
-  }
-
-  SemaphoreGuard guard(spi_mutex_);
-  if (!guard.take(pdMS_TO_TICKS(5000))) {
-    ESP_LOGE(TAG, "SPI mutex timeout for cmd with data 0x%02X", cmd);
-    return ESP_ERR_TIMEOUT;
-  }
-  err = dangerous_epd_write_cmd_without_lock_(cmd);
-  if (err != ESP_OK) {
-    return err;
-  };
-  for (size_t i = 0; i < data_len; ++i) {
-    err = dangerous_epd_write_data_without_lock_(data[i]);
-    if (err != ESP_OK) {
-      return err;
-    }
-  }
-  ESP_LOGI(TAG, "epd_write_cmd_with_data: cmd 0x%02X with %u bytes of data done", cmd, data_len);
-  return ESP_OK;
-}
-
-
-esp_err_t EPDHandler::dangerous_epd_write_cmd_without_lock_(const uint8_t cmd) {
-  ESP_LOGI(TAG, "dangerous_epd_write_cmd_without_lock_: sending 0x%02X", cmd);
-  gpio_set_level(PIN_DC, 0); // Command mode
-  spi_transaction_t t {};
-  t.length = 8;t.tx_buffer = &cmd;
-  esp_err_t err = spi_device_polling_transmit(spi_, &t);
-  if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to send data 0x%02X", cmd);
-  } else {
-    ESP_LOGI(TAG, "dangerous_epd_write_cmd_without_lock_: 0x%02X sent", cmd);
-  }
-  return err;
-}
-
-esp_err_t EPDHandler::dangerous_epd_write_data_without_lock_(const uint8_t data) {
-  ESP_LOGI(TAG, "dangerous_epd_write_data_without_lock_: sending 0x%02X", data);
-  gpio_set_level(PIN_DC, 1); // Data mode
-  spi_transaction_t t = { };
-  t.length = 8; t.tx_buffer = &data;
-  esp_err_t err = spi_device_polling_transmit(spi_, &t);
-  if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to send data 0x%02X", data);
-  } else {
-    ESP_LOGI(TAG, "dangerous_epd_write_data_without_lock_: 0x%02X sent", data);
-  }
-  return err;
-}
-
-esp_err_t EPDHandler::transfer_spi_data(const uint8_t* data, const size_t& length, uint32_t transaction_id, bool inverted) {
-  ESP_LOGI(TAG, "transfer_spi_data: waiting to send %zu bytes of data", length);
-
-  SemaphoreGuard transaction_guard(spi_transaction_mutex_);
-  esp_err_t err =
-    wait_for_transaction_end_(pdMS_TO_TICKS(5000), transaction_id, transaction_guard);
-  if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to wait for previous transaction end before sending data of %zu bytes: %s",
-      length, esp_err_to_name(err));
-    return err;
-  }
-  SemaphoreGuard guard(spi_mutex_);
-  if (!guard.take(pdMS_TO_TICKS(5000))) {
-    ESP_LOGE(TAG, "SPI mutex timeout for data transfer of %zu bytes", length);
-    return ESP_ERR_TIMEOUT;
-  }
-  ESP_LOGI(TAG, "transfer_spi_data: starting to send %zu bytes of data", length);
-
-  size_t offset = 0;
-  size_t remaining = length;
-  gpio_set_level(PIN_DC, 1); // Data mode
-
-  // Allocate a temporary buffer for inverted data (only if inverted)
-  uint8_t* temp_transfer_buffer = nullptr;
-  if (inverted) {
-    temp_transfer_buffer = (uint8_t*)heap_caps_malloc(DMA_TRANSFER_CHUNK_SIZE, MALLOC_CAP_DMA);
-    if (temp_transfer_buffer == nullptr) {
-      ESP_LOGE(TAG, "Failed to allocate memory for inverted data transfer buffer");
-      ESP_LOGI(TAG, "Current free heap size: %u bytes", esp_get_free_heap_size());
-      ESP_LOGI(TAG, "Current free DMA-capable memory size: %u bytes",
-        heap_caps_get_free_size(MALLOC_CAP_DMA));
-      return ESP_ERR_NO_MEM;
-    }
-  }
-
-  while (remaining > 0) {
-    size_t transfer_size = (remaining < DMA_TRANSFER_CHUNK_SIZE) ? remaining : DMA_TRANSFER_CHUNK_SIZE;
-
-    const uint8_t* transfer_buffer = nullptr;
-    if (inverted) {
-      // Invert only the current chunk into the temporary buffer
-      for (size_t i = 0; i < transfer_size; ++i) {
-        temp_transfer_buffer[i] = ~data[offset + i];
-      }
-      transfer_buffer = temp_transfer_buffer;
-    } else {
-      transfer_buffer = data + offset;
-    }
-
-    spi_transaction_t t = {};
-    t.length = transfer_size * 8;  // Length in bits
-    t.tx_buffer = transfer_buffer;
-
-    esp_err_t ret = spi_device_polling_transmit(spi_, &t);
-    if (ret != ESP_OK) {
-      ESP_LOGE(TAG, "Failed to send SPI chunk at offset %zu: %s", offset, esp_err_to_name(ret));
-      if (ret == ESP_ERR_NO_MEM) {
-        ESP_LOGE(TAG, "Current free heap size: %u bytes", esp_get_free_heap_size());
-        ESP_LOGE(TAG, "Current free DMA-capable memory size: %u bytes",
-          heap_caps_get_free_size(MALLOC_CAP_DMA));
-      }
-      if (inverted && temp_transfer_buffer != nullptr) {
-        // Free the temporary inverted buffer
-        heap_caps_free(temp_transfer_buffer);
-      }
-      return ret;
-    }
-
-    remaining -= transfer_size;
-    offset += transfer_size;
-
-    // Yield every 16KB to prevent watchdog timeout
-    if (offset % (16 * 1024) == 0) {
-      ESP_LOGI(TAG, "New data progress: %zu/%zu bytes sent, yielding...", offset, length);
-      vTaskDelay(pdMS_TO_TICKS(1));
-    }
-  }
-
-  if (inverted && temp_transfer_buffer != nullptr) {
-    // Free the temporary inverted buffer
-    heap_caps_free(temp_transfer_buffer);
-  }
-
-  ESP_LOGI(TAG, "transfer_spi_data: completed sending %zu bytes of data", length);
-  return ESP_OK;
-}
-
-esp_err_t EPDHandler::begin_transaction_(TickType_t timeout, uint32_t& out_id) {
-  ESP_LOGI(TAG, "begin_transaction_: waiting to obtain transaction mutex");
-  if (xSemaphoreTake(spi_transaction_mutex_, timeout) != pdTRUE) {
-    ESP_LOGE(TAG, "begin_transaction_: transaction mutex timeout");
-    return ESP_ERR_TIMEOUT;
-  }
-
-  out_id = ++spi_transaction_id;
-  ESP_LOGI(TAG, "begin_transaction_: transaction mutex obtained");
-  return ESP_OK;
-}
-
-esp_err_t EPDHandler::end_transaction_(void) {
-  ESP_LOGI(TAG, "end_transaction_: releasing transaction mutex");
-  if (xSemaphoreGive(spi_transaction_mutex_) != pdTRUE) {
-    ESP_LOGE(TAG, "end_transaction_: failed to release transaction mutex");
-    return ESP_FAIL;
-  }
-
-  ESP_LOGI(TAG, "end_transaction_: transaction mutex released");
-  return ESP_OK;
-}
-
-esp_err_t EPDHandler::wait_for_transaction_end_(TickType_t timeout, uint32_t awaiting_transaction_id, SemaphoreGuard& out_transaction_guard) {
-  // Validate transaction ID if provided
-  if (awaiting_transaction_id != 0 && awaiting_transaction_id != spi_transaction_id) {
-    // Invalid transaction ID
-    ESP_LOGE(TAG, "Invalid transaction ID 0x%08X while waiting, current transaction ID: 0x%08X",
-      awaiting_transaction_id, spi_transaction_id);
-    return ESP_ERR_INVALID_ARG;
-  }
-  SemaphoreGuard transaction_guard(spi_transaction_mutex_);
-  if (awaiting_transaction_id == 0) {
-    // wait for current transaction to complete
-    ESP_LOGV(TAG, "Waiting for current transaction 0x%08X to complete",
-      spi_transaction_id);
-    // take the mutex to ensure no transaction is active
-    if (!transaction_guard.take(timeout)) {
-      ESP_LOGE(TAG, "SPI transaction mutex timeout while waiting for transaction end");
-      return ESP_ERR_TIMEOUT;
-    }
-  }
-  // awaited_transaction_id is valid and matches current transaction ID or 0
-  out_transaction_guard = std::move(transaction_guard);
-  return ESP_OK;
-}

main/display/epd_handler.h

@@ -1,41 +0,0 @@
-#pragma once
-#include "freertos/FreeRTOS.h"
-#include "freertos/semphr.h"
-#include "driver/spi_master.h"
-#include "common/semaphore_guard.h"
-#include <vector>
-#include "display/transaction_guard.h"
-
-class EPDHandler : public WithTransaction {
-public:
-  EPDHandler();
-  ~EPDHandler();
-  esp_err_t init();
-
-  esp_err_t epd_write_cmd(const uint8_t cmd, uint32_t transaction_id);
-  esp_err_t epd_write_data(const uint8_t data, uint32_t transaction_id);
-  esp_err_t epd_write_cmd_with_data(const uint8_t cmd, std::vector<uint8_t>& data, uint32_t transaction_id);
-  esp_err_t transfer_spi_data(const uint8_t* data, const size_t& length, uint32_t transaction_id, bool inverted = false);
-
-  bool is_busy(void) const;
-  void wait_for_idle(void) const;
-
-private:
-
-  esp_err_t dangerous_epd_write_cmd_without_lock_(const uint8_t cmd);
-  esp_err_t dangerous_epd_write_data_without_lock_(const uint8_t data);
-
-  esp_err_t begin_transaction_(TickType_t timeout, uint32_t& out_id) override;
-  esp_err_t end_transaction_(void) override;
-  // given a transaction ID, wait for current transaction to complete. The transaction ID will determine if the wait is needed.
-  esp_err_t wait_for_transaction_end_(TickType_t timeout, uint32_t awaiting_transaction_id, SemaphoreGuard& out_transaction_guard);
-
-  spi_device_handle_t spi_ = nullptr;
-
-  SemaphoreHandle_t spi_mutex_ = nullptr;
-  SemaphoreHandle_t spi_transaction_mutex_ = nullptr;
-
-  uint32_t spi_transaction_id = 0; // For tracking SPI transactions
-
-  friend class TransactionGuard;
-};

main/display/lvgl_handler.cpp

@@ -11,7 +11,12 @@
 
 LVGLHandler::LVGLHandler(
   std::unique_ptr<EInkDisplayHandler> display_handler_in
-) : display_handler_(std::move(display_handler_in)) { }
+) : display_handler_(std::move(display_handler_in)) {
+  lvgl_mutex_ = xSemaphoreCreateMutex();
+  if (lvgl_mutex_ == nullptr) {
+    ESP_LOGE(TAG, "Failed to create LVGL mutex");
+  }
+}
 
 LVGLHandler::~LVGLHandler() {
   if (lvgl_display_ != nullptr) {
@@ -26,6 +31,14 @@ LVGLHandler::~LVGLHandler() {
     lv_draw_buf_destroy(lvgl_draw_buf_);
     lvgl_draw_buf_ = nullptr;
   }
+  if (framebuffer_ != nullptr) {
+    heap_caps_free(framebuffer_);
+    framebuffer_ = nullptr;
+  }
+  if (lvgl_mutex_ != nullptr) {
+    vSemaphoreDelete(lvgl_mutex_);
+    lvgl_mutex_ = nullptr;
+  }
 }
 
 esp_err_t LVGLHandler::initLVGL(EventGroupHandle_t system_event_group) {
@@ -90,64 +103,102 @@ void LVGLHandler::flush_cb_(lv_display_t* disp, const lv_area_t* area, uint8_t*
     return;
   }
   LVGLHandler* handler = static_cast<LVGLHandler*>(lv_display_get_user_data(disp));
-  if (handler == nullptr || handler->display_handler_ == nullptr) {
-    ESP_LOGE(TAG, "Invalid handler in flush callback");
+  if (handler == nullptr || handler->display_handler_ == nullptr || handler->framebuffer_ == nullptr) {
+    ESP_LOGE(TAG, "Invalid handler or framebuffer in flush callback");
     lv_display_flush_ready(disp);
     return;
   }
   uint8_t* pixel_data = px_map + 8; // Skip palette
   //
   ESP_LOGI(TAG, "Flush callback: x1=%d, y1=%d, x2=%d, y2=%d", area->x1, area->y1, area->x2, area->y2);
+  // take mutex
+  SemaphoreGuard guard(handler->lvgl_mutex_);
+  if (!guard.take(pdMS_TO_TICKS(5000))) {
+    ESP_LOGE(TAG, "LVGL mutex timeout in flush callback");
+    lv_display_flush_ready(disp);
+    return;
+  }
 
   // copy data to framebuffer
   int32_t area_w = lv_area_get_width(area);
   int32_t area_h = lv_area_get_height(area);
   if (area->x1 == 0 && area->y1 == 0 && area_w == DISPLAY_WIDTH && area_h == DISPLAY_HEIGHT) {
-    // revert the pixel data for e-ink (LVGL: 1=white, 0=black; E-Ink: 1=black, 0=white)
-    for (size_t i = 0; i < DISPLAY_BUFFER_SIZE; ++i) {
-      pixel_data[i] = ~pixel_data[i];
+    // Check if content actually changed before triggering expensive e-ink refresh
+    if (memcmp(handler->framebuffer_, pixel_data, DISPLAY_BUFFER_SIZE) == 0) {
+      ESP_LOGD(TAG, "Full screen flush with no changes - skipping e-ink refresh");
+      lv_display_flush_ready(disp);
+      return;
     }
-    esp_err_t err = handler->display_handler_->full_write(
-      pixel_data,
-      true  // white basemap
-    );
+    ESP_LOGI(TAG, "Full screen update");
+    memcpy(handler->framebuffer_, pixel_data, DISPLAY_BUFFER_SIZE);
+    // invert the framebuffer for e-ink display
+    for (size_t i = 0; i < DISPLAY_BUFFER_SIZE; ++i) {
+      handler->framebuffer_[i] = ~handler->framebuffer_[i];
+    }
+    // request full refresh
+    esp_err_t err = handler->display_handler_->full_write(handler->framebuffer_, true);
     if (err != ESP_OK) {
       ESP_LOGE(TAG, "Full refresh request failed: %s", esp_err_to_name(err));
     }
   } else {
     // partial update
     ESP_LOGI(TAG, "Partial update: x1=%d, y1=%d, w=%d, h=%d", area->x1, area->y1, area_w, area_h);
+    // update the framebuffer with the partial data
+    for (int32_t row = 0; row < area_h; ++row) {
+      int32_t fb_y = area->y1 + row;
+      int32_t fb_x_byte_start = area->x1 / 8;
+      int32_t fb_x_byte_end = area->x2 / 8;
+      uint8_t* fb_ptr = &handler->framebuffer_[fb_y * (DISPLAY_WIDTH / 8) + fb_x_byte_start];
+      const uint8_t* src_ptr = &pixel_data[row * (area_w / 8)];
+      // invert the partial framebuffer data for e-ink display
+      for (int32_t i = 0; i < (fb_x_byte_end - fb_x_byte_start + 1); ++i) {
+        fb_ptr[i] = ~src_ptr[i];
+      }
+    }
+    // update the refresh area
+    handler->refresh_area_.expand_to_include(area->x1, area->y1, area->x2, area->y2);
+    //
 
-    // Prepare partial buffer
-    const uint32_t area_width_bytes = (area->x2 - area->x1 + 1) / 8;
-    const uint32_t area_height = area->y2 - area->y1 + 1;
-    const size_t partial_buffer_size = area_width_bytes * area_height;
-    uint8_t* partial_buffer = new uint8_t[partial_buffer_size];
+    if (lv_display_flush_is_last(disp) && !handler->refresh_area_.is_empty()) {
+      ESP_LOGI(TAG, "Last flush in batch - performing partial refresh");
+      ESP_LOGI(TAG, "Refresh area: x1=%d, y1=%d, x2=%d, y2=%d",
+        handler->refresh_area_.x1, handler->refresh_area_.y1,
+        handler->refresh_area_.x2, handler->refresh_area_.y2);
+      // copy the area to refresh
+      uint8_t* partial_buffer = new uint8_t[handler->refresh_area_.area() / 8];
       if (partial_buffer == nullptr) {
-      ESP_LOGE(TAG, "Failed to allocate partial buffer for flush callback");
+        ESP_LOGE(TAG, "Failed to allocate partial buffer for refresh");
         lv_display_flush_ready(disp);
         return;
       }
-    // Copy pixel data to partial buffer and invert for e-ink
-    for (int32_t row = 0; row < area_height; ++row) {
-      for (int32_t col = 0; col < area_width_bytes; ++col) {
-        size_t src_index = row * area_width_bytes + col;
-        partial_buffer[src_index] = ~pixel_data[src_index];
+      // loop the refresh area and copy data
+      uint32_t x1 = handler->refresh_area_.x1;
+      uint32_t x2 = handler->refresh_area_.x2;
+      uint32_t y1 = handler->refresh_area_.y1;
+      uint32_t y2 = handler->refresh_area_.y2;
+      uint32_t height = y2 - y1 + 1;
+      uint32_t width = x2 - x1 + 1;
+
+      for (uint32_t row = 0; row < height; ++row) {
+        uint32_t fb_y = y1 + row;
+        uint32_t fb_x_byte_start = x1 / 8;
+        uint32_t fb_x_byte_end = x2 / 8;
+        uint8_t* fb_ptr = &handler->framebuffer_[fb_y * (DISPLAY_WIDTH / 8) + fb_x_byte_start];
+        uint8_t* dest_ptr = &partial_buffer[row * (width / 8)];
+        for (uint32_t i = 0; i < (fb_x_byte_end - fb_x_byte_start + 1); ++i) {
+          dest_ptr[i] = ~fb_ptr[i];
         }
       }
 
       esp_err_t err = handler->display_handler_->partial_refresh(partial_buffer,
-      RefreshArea {
-        area->x1,
-        area->y1,
-        area->x2,
-        area->y2
-      }, lv_display_flush_is_last(disp));
+        handler->refresh_area_);
       delete[] partial_buffer;
 
       if (err != ESP_OK) {
         ESP_LOGE(TAG, "Partial refresh request failed: %s", esp_err_to_name(err));
       }
+      handler->refresh_area_.reset();
+    }
   }
   //
   lv_display_flush_ready(disp);
@@ -183,7 +234,7 @@ void LVGLHandler::touch_read_cb_(lv_indev_t* indev, lv_indev_data_t* data) {
     esp_lcd_touch_get_data(tp_handle, point_data, &touch_cnt, 1);
 
     if (touch_cnt > 0) {
-      // ESP_LOGI(TAG, "Touch data read successfully: x=%d, y=%d", point_data[0].x, point_data[0].y);
+      ESP_LOGI(TAG, "Touch data read successfully: x=%d, y=%d", point_data[0].x, point_data[0].y);
       data->point.x = point_data[0].x;
       data->point.y = point_data[0].y;
       data->state = LV_INDEV_STATE_PRESSED;
@@ -217,10 +268,31 @@ esp_err_t LVGLHandler::initLVGLDisplay_() {
     return ESP_FAIL;
   }
 
+  // set framebuffer
+  framebuffer_ = (uint8_t*)heap_caps_malloc(LVGL_BUFFER_SIZE, MALLOC_CAP_SPIRAM);
+  if (framebuffer_ != nullptr) {
+    framebuffer_in_psram_ = true;
+    ESP_LOGI(TAG, "Framebuffer allocated in PSRAM (%zu bytes)", LVGL_BUFFER_SIZE);
+  } else {
+    ESP_LOGW(TAG, "PSRAM not available, allocating framebuffer in internal RAM");
+    framebuffer_ = (uint8_t*)heap_caps_malloc(LVGL_BUFFER_SIZE, MALLOC_CAP_INTERNAL);
+    framebuffer_in_psram_ = false;
+    if (framebuffer_ == nullptr) {
+      ESP_LOGE(TAG, "Failed to allocate framebuffer");
+      lv_display_delete(lvgl_display_);
+      lvgl_display_ = nullptr;
+      lvgl_port_unlock();
+      return ESP_FAIL;
+    }
+    ESP_LOGI(TAG, "Framebuffer allocated in internal RAM (%zu bytes)", LVGL_BUFFER_SIZE);
+  }
+  memset(framebuffer_, 0xFF, LVGL_BUFFER_SIZE);  // Initialize to white
   // Create a draw buffer covering the entire display
   lvgl_draw_buf_ = lv_draw_buf_create(DISPLAY_WIDTH, DISPLAY_HEIGHT, LV_COLOR_FORMAT_I1, LV_STRIDE_AUTO);
   if (lvgl_draw_buf_ == nullptr) {
     ESP_LOGE(TAG, "Failed to create LVGL draw buffer");
+    heap_caps_free(framebuffer_);
+    framebuffer_ = nullptr;
     lv_display_delete(lvgl_display_);
     lvgl_display_ = nullptr;
     lvgl_port_unlock();

main/display/lvgl_handler.h

@@ -31,4 +31,10 @@ private:
   lv_display_t* lvgl_display_ = nullptr;
   lv_indev_t* lvgl_touch_indev_ = nullptr;
   lv_draw_buf_t* lvgl_draw_buf_ = nullptr;
+  uint8_t* framebuffer_ = nullptr;
+  bool framebuffer_in_psram_ = false;
+  RefreshArea refresh_area_ = { 0, 0, 0, 0 };
+
+
+  SemaphoreHandle_t lvgl_mutex_ = nullptr;
 };

main/display/transaction_guard.h

@@ -1,33 +0,0 @@
-#pragma once
-#include "freertos/FreeRTOS.h"
-#include "freertos/semphr.h"
-#include <esp_err.h>
-#include <type_traits>
-
-class WithTransaction {
-protected:
-  virtual esp_err_t end_transaction_() = 0;
-  virtual esp_err_t begin_transaction_(TickType_t timeout, uint32_t& out_id) = 0;
-
-  friend class TransactionGuard;
-};
-
-class TransactionGuard {
-public:
-  TransactionGuard(WithTransaction& handler, TickType_t timeout = portMAX_DELAY)
-    : handler_(handler) { }
-  ~TransactionGuard() { if (transaction_id_) handler_.end_transaction_(); }
-
-  esp_err_t begin(TickType_t timeout = portMAX_DELAY) {
-    esp_err_t err = handler_.begin_transaction_(timeout, transaction_id_);
-    return err;
-  }
-  uint32_t transaction_id() const { return transaction_id_; }
-  bool is_active() const { return transaction_id_ != 0; }
-private:
-  // delete copy constructor and assignment operator
-  TransactionGuard(const TransactionGuard&) = delete;
-  TransactionGuard& operator=(const TransactionGuard&) = delete;
-  WithTransaction& handler_;
-  uint32_t transaction_id_ = 0;
-};

main/info/info.cpp

@@ -23,8 +23,7 @@ void display_chip_info() {
     (chip_info.features & CHIP_FEATURE_BLE) ? "BLE" : "",
     (chip_info.features & CHIP_FEATURE_IEEE802154) ? ", 802.15.4 (Zigbee/Thread), " : "",
     // psram
-    (chip_info.features & CHIP_FEATURE_EMB_PSRAM) ? "with embedded PSRAM, " : ""
-  );
+    (chip_info.features & CHIP_FEATURE_EMB_PSRAM) ? "with embedded PSRAM, " : "");
 
   unsigned major_rev = chip_info.revision / 100;
   unsigned minor_rev = chip_info.revision % 100;
@@ -40,8 +39,5 @@ void display_chip_info() {
   printf("Minimum free heap size: %" PRIu32 " bytes\n", esp_get_minimum_free_heap_size());
   // psram
   printf("PSRAM size: %u bytes\n", esp_psram_get_size());
-  // dma size
-  printf("DMA-capable memory size: %u bytes\n", heap_caps_get_free_size(MALLOC_CAP_DMA));
-  printf("DMA-capable internal memory size: %u bytes\n", heap_caps_get_free_size(MALLOC_CAP_DMA | MALLOC_CAP_INTERNAL));
 
 }

main/io/nvs_handler.cpp

@@ -20,7 +20,6 @@ NVSStorageHandler::~NVSStorageHandler() {
 void NVSStorageHandler::init(const EventGroupHandle_t& system_event_group) {
   esp_err_t err = nvs_flash_init();
   if (err == ESP_ERR_NVS_NO_FREE_PAGES || err == ESP_ERR_NVS_NEW_VERSION_FOUND) {
-    ESP_LOGW(TAG, "NVS Flash init failed with %s, erasing and retrying...", esp_err_to_name(err));
     nvs_flash_erase();
     err = nvs_flash_init();
   }
@@ -44,26 +43,11 @@ void NVSStorageHandler::put(const std::string& key, const std::string& value) {
   }
 
   esp_err_t err = nvs_set_str(this->nvsHandle, key.c_str(), value.c_str());
-  if (err == ESP_ERR_NVS_NOT_ENOUGH_SPACE) {
-    ESP_LOGE(TAG, "NVS storage full! Cannot store key '%s'. Consider clearing old data.", key.c_str());
-    ESP_LOGI(TAG, "Attempting to erase and retry...");
-    // Try to commit pending changes first
-    nvs_commit(this->nvsHandle);
-    // Retry once
-    err = nvs_set_str(this->nvsHandle, key.c_str(), value.c_str());
   if (err != ESP_OK) {
-      ESP_LOGE(TAG, "Retry failed: %s", esp_err_to_name(err));
-      return;
-    }
-  } else if (err != ESP_OK) {
     ESP_LOGE(TAG, "Error (%s) setting key-value pair in NVS!", esp_err_to_name(err));
-    return;
-  }
-
-  // Commit successful write
-  err = nvs_commit(this->nvsHandle);
-  if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Error (%s) committing to NVS!", esp_err_to_name(err));
+  } else {
+    nvs_commit(this->nvsHandle);
+    // ESP_LOGI(TAG, "Key-value pair (%s, %s) stored in NVS.", key.c_str(), value.c_str());
   }
 }
 

main/main.cpp

@@ -42,6 +42,221 @@ void init_queues(
   EventGroupHandle_t& system_lifecycle_event_group
 );
 
+
+
+void EInk_Checkerboard(
+  EInkDisplayHandler* display_handler
+) {
+  struct CheckerboardTaskParams {
+    EInkDisplayHandler* display_handler;
+  };
+  auto checkerboard_task_fn = [](void* pvParameters) {
+    CheckerboardTaskParams* params = static_cast<CheckerboardTaskParams*>(pvParameters);
+    if (params != nullptr && params->display_handler != nullptr) {
+      // Add this task to the watchdog timer
+      esp_err_t wdt_err = esp_task_wdt_add(NULL);
+      if (wdt_err != ESP_OK) {
+        ESP_LOGW(TAG, "Failed to add checkerboard task to watchdog: %s", esp_err_to_name(wdt_err));
+      }
+
+      EInkDisplayHandler* display_handler = params->display_handler;
+      const size_t DISPLAY_BUFFER_SIZE = DISPLAY_WIDTH * DISPLAY_HEIGHT / 8;
+      uint8_t* framebuffer = new uint8_t[DISPLAY_BUFFER_SIZE];
+      if (framebuffer == nullptr) {
+        ESP_LOGE(TAG, "Failed to allocate framebuffer for checkerboard task");
+        if (wdt_err == ESP_OK) {
+          esp_task_wdt_delete(NULL);
+        }
+        vTaskDelete(NULL);
+        return;
+      }
+      // Create checkerboard pattern
+      for (size_t y = 0; y < DISPLAY_HEIGHT; y++) {
+        for (size_t x = 0; x < DISPLAY_WIDTH; x++) {
+          size_t byte_index = (y * DISPLAY_WIDTH + x) / 8;
+          size_t bit_index = 7 - (x % 8);
+          bool is_white = ((x / 20) % 2) == ((y / 20) % 2);
+          if (is_white) {
+            framebuffer[byte_index] |= (1 << bit_index); // Set bit to 1 for white
+          } else {
+            framebuffer[byte_index] &= ~(1 << bit_index); // Clear bit to 0 for black
+          }
+        }
+        // Yield and reset watchdog periodically
+        const size_t YIELD_INTERVAL = 16;
+        if (y % YIELD_INTERVAL == 0) {
+          if (wdt_err == ESP_OK) {
+            esp_task_wdt_reset();
+          }
+          vTaskDelay(1 / portTICK_PERIOD_MS);
+          // partial refresh to show progress
+          int32_t y_start = static_cast<int32_t>((y >= YIELD_INTERVAL - 1) ? (y - (YIELD_INTERVAL - 1)) : 0);
+          int32_t y_end = static_cast<int32_t>(y);
+          // get the partial framebuffer for this area
+          uint8_t* partial_framebuffer = &framebuffer[y_start * (DISPLAY_WIDTH / 8)];
+          esp_err_t err = display_handler->partial_refresh(partial_framebuffer, RefreshArea { 0, y_start, DISPLAY_WIDTH - 1, y_end });
+          if (err != ESP_OK) {
+            ESP_LOGE(TAG, "Partial refresh failed at y=%d: %s", y, esp_err_to_name(err));
+          }
+          // wait for 4 seconds to prevent spamming the display
+          // vTaskDelay(2000 / portTICK_PERIOD_MS);
+        }
+      }
+      // Perform full write to display
+      // esp_err_t err = display_handler->full_write(framebuffer);
+      // if (err != ESP_OK) {
+      //   ESP_LOGE(TAG, "Checkerboard full write failed: %s", esp_err_to_name(err));
+      // } else {
+      //   ESP_LOGI(TAG, "Checkerboard pattern displayed successfully.");
+      // }
+      delete[] framebuffer;
+
+      // Remove task from watchdog before deletion
+      if (wdt_err == ESP_OK) {
+        esp_task_wdt_delete(NULL);
+      }
+    } else {
+      ESP_LOGE(TAG, "Invalid parameters for checkerboard task");
+    }
+    vTaskDelete(NULL);
+    };
+  CheckerboardTaskParams* checker_params = new CheckerboardTaskParams();
+  checker_params->display_handler = display_handler;
+  BaseType_t res = xTaskCreate(
+    checkerboard_task_fn,
+    "checkerboard_task",
+    8192,
+    static_cast<void*>(checker_params),
+    tskIDLE_PRIORITY + 1,
+    NULL
+  );
+
+  if (res != pdPASS) {
+    ESP_LOGE(TAG, "Failed to create checkerboard task");
+    delete checker_params;
+  }
+}
+
+void LVGL_Checkerboard(
+  LVGLHandler* lvgl_handler
+) {
+  struct CheckerboardTaskParams {
+    LVGLHandler* lvgl_handler;
+  };
+  auto checkerboard_task_fn = [](void* pvParameters) {
+    CheckerboardTaskParams* params = static_cast<CheckerboardTaskParams*>(pvParameters);
+    if (params == nullptr || params->lvgl_handler == nullptr) {
+      ESP_LOGE(TAG, "Invalid parameters for LVGL checkerboard task");
+      delete params;
+      vTaskDelete(NULL);
+      return;
+    }
+    auto* handler = static_cast<LVGLHandler*>(params->lvgl_handler);
+
+    // Add safety checks
+    if (!handler) {
+      ESP_LOGE("LVGL", "Handler is null!");
+      delete params;
+      vTaskDelete(NULL);
+      return;
+    }
+
+    ESP_LOGI("HEAP", "Free: %d", esp_get_free_heap_size());
+
+    // Wait for LVGL system to fully initialize
+    vTaskDelay(pdMS_TO_TICKS(200));
+
+    // Acquire LVGL lock with proper timeout
+    if (!lvgl_port_lock(pdMS_TO_TICKS(5000))) {
+      ESP_LOGE(TAG, "Failed to acquire LVGL lock for checkerboard");
+      delete params;
+      vTaskDelete(NULL);
+      return;
+    }
+
+    // Verify LVGL is properly initialized
+    if (lv_display_get_default() == nullptr) {
+      ESP_LOGE(TAG, "LVGL default display not available");
+      lvgl_port_unlock();
+      delete params;
+      vTaskDelete(NULL);
+      return;
+    }
+
+    // Create LVGL objects for checkerboard
+    lv_obj_t* scr = lv_scr_act();
+    if (scr == nullptr) {
+      ESP_LOGE(TAG, "Failed to get active LVGL screen");
+      lvgl_port_unlock();
+      delete params;
+      vTaskDelete(NULL);
+      return;
+    }
+    lv_obj_t* checkerboard = lv_obj_create(scr);
+    if (checkerboard == nullptr) {
+      ESP_LOGE(TAG, "Failed to create LVGL checkerboard object");
+      lvgl_port_unlock();
+      delete params;
+      vTaskDelete(NULL);
+      return;
+    }
+    lv_obj_set_size(checkerboard, DISPLAY_WIDTH, DISPLAY_HEIGHT);
+    // remove border and padding
+    lv_obj_set_style_pad_all(checkerboard, 0, 0);
+    lv_obj_set_style_border_width(checkerboard, 0, 0);
+    const int CELL_SIZE = 40;
+    lvgl_port_unlock();
+    // Create checkerboard pattern using LVGL
+    for (int y = 0; y < DISPLAY_HEIGHT; y += CELL_SIZE) {
+      lvgl_port_lock(pdMS_TO_TICKS(1000));
+      for (int x = 0; x < DISPLAY_WIDTH; x += CELL_SIZE) {
+        lv_color_t color = (((x / CELL_SIZE) % 2) == ((y / CELL_SIZE) % 2)) ? lv_color_hex(0xFFFFFF) : lv_color_hex(0x000000);
+        lv_obj_t* cell = lv_obj_create(checkerboard);
+        if (cell == nullptr) {
+          ESP_LOGE(TAG, "Failed to create LVGL checkerboard cell");
+          lvgl_port_unlock();
+          continue;
+        }
+        lv_obj_set_size(cell, CELL_SIZE, CELL_SIZE);
+        lv_obj_set_style_bg_color(cell, color, 0);
+        lv_obj_set_pos(cell, x, y);
+        // remove border and padding
+        lv_obj_set_style_pad_all(cell, 0, 0);
+        lv_obj_set_style_border_width(cell, 0, 0);
+        lv_obj_t* label = lv_label_create(cell);
+        if (label != nullptr) {
+          lv_label_set_text_fmt(label, "(%d,%d)", x, y);
+          lv_obj_center(label);
+        }
+      }
+      lvgl_port_unlock();
+      // Yield to allow LVGL to process rendering
+      vTaskDelay(5000 / portTICK_PERIOD_MS);
+    }
+
+
+
+    ESP_LOGI(TAG, "LVGL Checkerboard pattern displayed successfully.");
+    delete params;
+    vTaskDelete(NULL);
+    };
+  CheckerboardTaskParams* checker_params = new CheckerboardTaskParams();
+  checker_params->lvgl_handler = lvgl_handler;
+  BaseType_t res = xTaskCreate(
+    checkerboard_task_fn,
+    "lvgl_checkerboard_task",
+    8192,
+    static_cast<void*>(checker_params),
+    tskIDLE_PRIORITY + 1,
+    NULL
+  );
+  if (res != pdPASS) {
+    ESP_LOGE(TAG, "Failed to create LVGL checkerboard task");
+    delete checker_params;
+  }
+}
+
+
 void app_main(void) {
   display_chip_info();
 
@@ -57,14 +272,14 @@ void app_main(void) {
   ESP_LOGI(TAG, "Queues initialized.\n");
 
   //
-  KVStorageHandler* kv_storage_handler = new NVSStorageHandler(
-    DEFAULT_STORAGE_NAMESPACE
-  );
+  // KVStorageHandler* kv_storage_handler = new NVSStorageHandler(
+  //   DEFAULT_STORAGE_NAMESPACE
+  // );
 
-  auto wifi_handler = std::make_unique<WifiHandler>(
-    std::unique_ptr<KVStorageHandler>(new NVSStorageHandler(WIFI_CREDENTIALS_STORAGE_NAMESPACE))
-  );
-  NetworkHandler* network_handler = new NetworkHandler(std::move(wifi_handler));
+  // auto wifi_handler = std::make_unique<WifiHandler>(
+  //   std::unique_ptr<KVStorageHandler>(new NVSStorageHandler(WIFI_CREDENTIALS_STORAGE_NAMESPACE))
+  // );
+  // NetworkHandler* network_handler = new NetworkHandler(std::move(wifi_handler));
   EInkDisplayHandler* display_handler = new EInkDisplayHandler();
   // Initialize display and touch
   // display_handler->init_devices(system_event_group);
@@ -81,8 +296,8 @@ void app_main(void) {
   }
 
   //
-  kv_storage_handler->init(system_event_group);
-  network_handler->init(system_event_group);
+  // kv_storage_handler->init(system_event_group);
+  // network_handler->init(system_event_group);
 
   //
   ESP_LOGI(TAG, "Waiting for system to be ready...\n");
@@ -97,73 +312,39 @@ void app_main(void) {
   );
   ESP_LOGI(TAG, "System is ready. Starting main application...\n");
 
-  DiscordAppDescriptor::instance();
-  UIHandler ui_handler;
-  err = ui_handler.init();
-  if (err != ESP_OK) {
-    ESP_LOGE(TAG, "Failed to initialize UI handler: %s", esp_err_to_name(err));
-    vTaskDelay(5000 / portTICK_PERIOD_MS);
-    return esp_restart();
-  }
-  ESP_LOGI(TAG, "UI handler initialized.\n");
-
   // Allow LVGL system to stabilize before creating objects
   vTaskDelay(pdMS_TO_TICKS(100));
 
-  // Create main screen and button for random rectangle demo
-  // lv_obj_t* scr = lv_scr_act();
+  // Show checkerboard pattern on display for testing
+  // EInk_Checkerboard(display_handler);
+  LVGL_Checkerboard(&lvgl_handler);
 
-  // // Create a button
-  // lv_obj_t* btn = lv_btn_create(scr);
-  // lv_obj_set_size(btn, 200, 60);
-  // lv_obj_align(btn, LV_ALIGN_TOP_MID, 0, 20);
-  // lv_obj_set_style_border_width(btn, 2, 0);
-  // lv_obj_set_style_border_color(btn, lv_color_make(0, 0, 0), 0);
+  // Register apps with AppRegistry by creating their descriptors
+  // Each descriptor will create and register the app instance
+  // DemoAppDescriptor* demo_descriptor = new DemoAppDescriptor();
+  // ShutdownAppDescriptor* shutdown_descriptor = new ShutdownAppDescriptor();
+  // DiscordAppDescriptor::instance(); // Use singleton pattern for Discord app
+  // MtrAppDescriptor* mtr_descriptor = new MtrAppDescriptor();
 
-  // // Add label to button
-  // lv_obj_t* label = lv_label_create(btn);
-  // lv_label_set_text(label, "Create Random Rect");
-  // lv_obj_center(label);
-  // lv_obj_set_style_text_color(label, lv_color_make(0, 0, 0), 0);
+  // Pass network handler to MtrApp so it can fetch arrival data
+  // MtrApp* mtr_app = dynamic_cast<MtrApp*>(mtr_descriptor->get_app_instance());
+  // if (mtr_app) {
+  //   mtr_app->set_network_handler(network_handler);
+  // }
 
-  // // Event handler for button - creates random rectangles
-  // auto btn_event_cb = [](lv_event_t* e) {
-  //   lv_obj_t* scr = lv_scr_act();
+  // ESP_LOGI(TAG, "Apps registered with AppRegistry\n");
 
-  //   // Create a random rectangle
-  //   lv_obj_t* rect = lv_obj_create(scr);
+  // Initialize UI Handler (will render app icons from registry)
+  // UIHandler ui_handler;
+  // if (ui_handler.init() != ESP_OK) {
+  //   ESP_LOGE(TAG, "Failed to initialize UI handler");
+  //   vTaskDelay(5000 / portTICK_PERIOD_MS);
+  //   return esp_restart();
+  // }
+  // ESP_LOGI(TAG, "UI handler initialized successfully\n");
+  // ESP_LOGI(TAG, "Main screen displayed with app icons. Tap an icon to launch an app.\n");
 
-  //   // Random size (30-100 pixels)
-  //   lv_coord_t width = 30 + (esp_random() % 70);
-  //   lv_coord_t height = 30 + (esp_random() % 70);
-  //   lv_obj_set_size(rect, width, height);
 
-  //   // Random position (avoid top 100px where button is)
-  //   lv_coord_t x = esp_random() % (LV_HOR_RES - width);
-  //   lv_coord_t y = 100 + (esp_random() % (LV_VER_RES - 100 - height));
-  //   lv_obj_set_pos(rect, x, y);
-
-  //   lv_obj_set_style_bg_color(rect, lv_color_make(0, 0, 0), 0);
-  //   lv_obj_set_style_bg_opa(rect, LV_OPA_COVER, 0);
-
-  //   // Make rectangle clickable
-  //   lv_obj_add_flag(rect, LV_OBJ_FLAG_CLICKABLE);
-
-  //   // Event handler to delete rectangle when clicked
-  //   auto rect_event_cb = [](lv_event_t* e) {
-  //     lv_obj_t* rect = static_cast<lv_obj_t*>(lv_event_get_target(e));
-  //     lv_obj_del(rect);
-  //     ESP_LOGI(TAG, "Rectangle deleted");
-  //     };
-
-  //   lv_obj_add_event_cb(rect, rect_event_cb, LV_EVENT_CLICKED, NULL);
-
-  //   ESP_LOGI(TAG, "Created rectangle at (%d, %d) with size %dx%d", x, y, width, height);
-  //   };
-
-  // lv_obj_add_event_cb(btn, btn_event_cb, LV_EVENT_CLICKED, NULL);
-
-  // ESP_LOGI(TAG, "Random rectangle demo initialized. Tap button to create rectangles.\n");
 
   // wait for shutdown signal
   ESP_LOGI(TAG, "Waiting for shutdown signal...\n");

main/network/wifi_handler.cpp

@@ -160,7 +160,6 @@ esp_err_t WifiHandler::connect(const std::string& ssid, const std::string& passw
     this->current_ssid.clear();
   }
   this->current_ssid = ssid;
-  this->current_password = password;
 
   //
   wifi_config_t wifi_config = {};
@@ -183,8 +182,8 @@ esp_err_t WifiHandler::connect(const std::string& ssid, const std::string& passw
     return err;
   }
 
-  // Note: Credentials will be stored in the event handler after successful connection
-  // to avoid storing credentials for failed connection attempts
+  // store credentials after successful connection attempt
+  this->store_wifi_credentials(this->current_ssid, password);
 
   return ESP_OK;
 }
@@ -306,10 +305,6 @@ void WifiHandler::wifi_event_handler(void* arg, esp_event_base_t event_base, int
         self->s_wifi_event_group,
         WIFI_CONNECTED_BIT
       );
-      // Store credentials only after successful connection
-      if (!self->current_ssid.empty() && !self->current_password.empty()) {
-        self->store_wifi_credentials(self->current_ssid, self->current_password);
-      }
       break;
     }
     default:
@@ -333,11 +328,7 @@ void WifiHandler::store_wifi_credentials(const std::string& ssid, const std::str
     ESP_LOGE(TAG, "Failed to take credential mutex");
     return;
   }
-
-  // Store current SSID
-  kvs->put(WIFI_SSID_KEY, ssid);
-
-  // Store the password according to the JSON structure
+  // store the password according to the JSON structure
   std::string password_key_store = kvs->get(WIFI_PASSWORD_STORE_KEY);
   cJSON* json = nullptr;
   if (password_key_store.empty()) {
@@ -357,37 +348,17 @@ void WifiHandler::store_wifi_credentials(const std::string& ssid, const std::str
     credentials = cJSON_CreateObject();
     cJSON_AddItemToObject(json, "credentials", credentials);
   }
-
-  // Limit stored credentials to prevent NVS overflow (keep max 10 SSIDs)
-  int credential_count = cJSON_GetArraySize(credentials);
-  if (credential_count >= 10) {
-    ESP_LOGW(TAG, "Too many stored credentials (%d), clearing old ones", credential_count);
-    // Keep only the current SSID's credentials, clear others
-    cJSON_DeleteItemFromObject(credentials, ssid.c_str()); // Remove if exists
-    cJSON* new_credentials = cJSON_CreateObject();
-    cJSON_ReplaceItemInObject(json, "credentials", new_credentials);
-    credentials = new_credentials;
-  }
-
-  // Remove existing entry for this SSID to update it
-  cJSON_DeleteItemFromObject(credentials, ssid.c_str());
-
   // create SSID object
   cJSON* ssid_item = cJSON_CreateObject();
   // add password field
   cJSON_AddStringToObject(ssid_item, "password", password.c_str());
   // add SSID object to credentials
   cJSON_AddItemToObject(credentials, ssid.c_str(), ssid_item);
-
   // store updated JSON string
   char* updated_json_str = cJSON_PrintUnformatted(json);
   if (updated_json_str) {
-    esp_err_t err = ESP_OK;
     kvs->put(WIFI_PASSWORD_STORE_KEY, std::string(updated_json_str));
-    // Note: Error handling is done in nvs_handler.cpp put() method
     cJSON_free(updated_json_str);
-  } else {
-    ESP_LOGE(TAG, "Failed to serialize WiFi credentials JSON");
   }
   cJSON_Delete(json);
 }

main/network/wifi_handler.h

@@ -51,8 +51,6 @@ private:
   SemaphoreHandle_t credential_mutex = nullptr;
   // current connected / preferred SSID
   std::string current_ssid;
-  // current password (temporarily stored for successful connection event)
-  std::string current_password;
   // prevent auto-reconnect on expected disconnection, e.g. when user calls disconnect()
   // should be reset to false after connect()
   bool expect_disconnected = false;

partitions.csv

@@ -1,12 +0,0 @@
-# Name,   Type, SubType,  Offset,   Size,       Flags
-# NVS 256KB
-nvs,      data, nvs,      ,         0x40000,
-# OTA Data 8KB
-otadata,  data, ota,      ,         0x2000,
-# PHY Init 4KB
-phy_init, data, phy,      ,         0x1000,
-# OTA Partitions 10MB
-ota_0,    app,  ota_0,    ,         0xA00000,
-ota_1,    app,  ota_1,    ,         0xA00000,
-# SPIFFS 11MB
-storage,  data, spiffs,   ,         0xB00000,

sdkconfig.default

@@ -430,9 +430,9 @@ CONFIG_BOOTLOADER_APP_ROLLBACK_ENABLE=y
 # end of Recovery Bootloader and Rollback
 
 CONFIG_BOOTLOADER_OFFSET_IN_FLASH=0x0
-# CONFIG_BOOTLOADER_COMPILER_OPTIMIZATION_SIZE is not set
+CONFIG_BOOTLOADER_COMPILER_OPTIMIZATION_SIZE=y
 # CONFIG_BOOTLOADER_COMPILER_OPTIMIZATION_DEBUG is not set
-CONFIG_BOOTLOADER_COMPILER_OPTIMIZATION_PERF=y
+# CONFIG_BOOTLOADER_COMPILER_OPTIMIZATION_PERF is not set
 # CONFIG_BOOTLOADER_COMPILER_OPTIMIZATION_NONE is not set
 
 #
@@ -469,7 +469,8 @@ CONFIG_BOOTLOADER_LOG_MODE_TEXT=y
 # CONFIG_BOOTLOADER_FLASH_DC_AWARE is not set
 CONFIG_BOOTLOADER_FLASH_XMC_SUPPORT=y
 CONFIG_BOOTLOADER_FLASH_32BIT_ADDR=y
-CONFIG_BOOTLOADER_CACHE_32BIT_ADDR_OCTAL_FLASH=y
+CONFIG_BOOTLOADER_FLASH_NEEDS_32BIT_FEAT=y
+CONFIG_BOOTLOADER_FLASH_NEEDS_32BIT_ADDR_QUAD_FLASH=y
 # end of Serial Flash Configurations
 
 CONFIG_BOOTLOADER_VDDSDIO_BOOST_1_9V=y
@@ -551,12 +552,14 @@ CONFIG_BOOT_ROM_LOG_ALWAYS_ON=y
 # Serial flasher config
 #
 # CONFIG_ESPTOOLPY_NO_STUB is not set
-CONFIG_ESPTOOLPY_OCT_FLASH=y
+# CONFIG_ESPTOOLPY_OCT_FLASH is not set
 CONFIG_ESPTOOLPY_FLASH_MODE_AUTO_DETECT=y
-CONFIG_ESPTOOLPY_FLASHMODE_OPI=y
+# CONFIG_ESPTOOLPY_FLASHMODE_QIO is not set
+# CONFIG_ESPTOOLPY_FLASHMODE_QOUT is not set
+CONFIG_ESPTOOLPY_FLASHMODE_DIO=y
+# CONFIG_ESPTOOLPY_FLASHMODE_DOUT is not set
 CONFIG_ESPTOOLPY_FLASH_SAMPLE_MODE_STR=y
-# CONFIG_ESPTOOLPY_FLASH_SAMPLE_MODE_DTR is not set
-CONFIG_ESPTOOLPY_FLASHMODE="dout"
+CONFIG_ESPTOOLPY_FLASHMODE="dio"
 # CONFIG_ESPTOOLPY_FLASHFREQ_120M is not set
 CONFIG_ESPTOOLPY_FLASHFREQ_80M=y
 # CONFIG_ESPTOOLPY_FLASHFREQ_40M is not set
@@ -1105,14 +1108,14 @@ CONFIG_SPIRAM_SPEED=80
 CONFIG_SPIRAM_BOOT_HW_INIT=y
 CONFIG_SPIRAM_BOOT_INIT=y
 CONFIG_SPIRAM_PRE_CONFIGURE_MEMORY_PROTECTION=y
-# CONFIG_SPIRAM_IGNORE_NOTFOUND is not set
+CONFIG_SPIRAM_IGNORE_NOTFOUND=y
 # CONFIG_SPIRAM_USE_MEMMAP is not set
 # CONFIG_SPIRAM_USE_CAPS_ALLOC is not set
 CONFIG_SPIRAM_USE_MALLOC=y
-CONFIG_SPIRAM_MEMTEST=y
+# CONFIG_SPIRAM_MEMTEST is not set
 CONFIG_SPIRAM_MALLOC_ALWAYSINTERNAL=16384
 CONFIG_SPIRAM_TRY_ALLOCATE_WIFI_LWIP=y
-CONFIG_SPIRAM_MALLOC_RESERVE_INTERNAL=65536
+CONFIG_SPIRAM_MALLOC_RESERVE_INTERNAL=32768
 # CONFIG_SPIRAM_ALLOW_BSS_SEG_EXTERNAL_MEMORY is not set
 # CONFIG_SPIRAM_ALLOW_NOINIT_SEG_EXTERNAL_MEMORY is not set
 # end of SPI RAM config
@@ -1266,9 +1269,9 @@ CONFIG_ESP_WIFI_ENABLED=y
 CONFIG_ESP_WIFI_STATIC_RX_BUFFER_NUM=10
 CONFIG_ESP_WIFI_DYNAMIC_RX_BUFFER_NUM=32
 CONFIG_ESP_WIFI_STATIC_TX_BUFFER=y
+# CONFIG_ESP_WIFI_DYNAMIC_TX_BUFFER is not set
 CONFIG_ESP_WIFI_TX_BUFFER_TYPE=0
 CONFIG_ESP_WIFI_STATIC_TX_BUFFER_NUM=16
-CONFIG_ESP_WIFI_CACHE_TX_BUFFER_NUM=32
 CONFIG_ESP_WIFI_STATIC_RX_MGMT_BUFFER=y
 # CONFIG_ESP_WIFI_DYNAMIC_RX_MGMT_BUFFER is not set
 CONFIG_ESP_WIFI_DYNAMIC_RX_MGMT_BUF=0
@@ -1278,15 +1281,14 @@ CONFIG_ESP_WIFI_AMPDU_TX_ENABLED=y
 CONFIG_ESP_WIFI_TX_BA_WIN=6
 CONFIG_ESP_WIFI_AMPDU_RX_ENABLED=y
 CONFIG_ESP_WIFI_RX_BA_WIN=6
-# CONFIG_ESP_WIFI_AMSDU_TX_ENABLED is not set
 CONFIG_ESP_WIFI_NVS_ENABLED=y
 # CONFIG_ESP_WIFI_TASK_PINNED_TO_CORE_0 is not set
 CONFIG_ESP_WIFI_TASK_PINNED_TO_CORE_1=y
 CONFIG_ESP_WIFI_SOFTAP_BEACON_MAX_LEN=752
 CONFIG_ESP_WIFI_MGMT_SBUF_NUM=32
-# CONFIG_ESP_WIFI_IRAM_OPT is not set
+CONFIG_ESP_WIFI_IRAM_OPT=y
 # CONFIG_ESP_WIFI_EXTRA_IRAM_OPT is not set
-# CONFIG_ESP_WIFI_RX_IRAM_OPT is not set
+CONFIG_ESP_WIFI_RX_IRAM_OPT=y
 CONFIG_ESP_WIFI_ENABLE_WPA3_SAE=y
 CONFIG_ESP_WIFI_ENABLE_SAE_PK=y
 CONFIG_ESP_WIFI_ENABLE_SAE_H2E=y
@@ -1566,7 +1568,6 @@ CONFIG_LWIP_TCP_OOSEQ_MAX_PBUFS=4
 CONFIG_LWIP_TCP_OVERSIZE_MSS=y
 # CONFIG_LWIP_TCP_OVERSIZE_QUARTER_MSS is not set
 # CONFIG_LWIP_TCP_OVERSIZE_DISABLE is not set
-# CONFIG_LWIP_WND_SCALE is not set
 CONFIG_LWIP_TCP_RTO_TIME=1500
 # end of TCP
 
@@ -1670,9 +1671,9 @@ CONFIG_LWIP_HOOK_IP6_INPUT_DEFAULT=y
 #
 # mbedTLS
 #
-# CONFIG_MBEDTLS_INTERNAL_MEM_ALLOC is not set
+CONFIG_MBEDTLS_INTERNAL_MEM_ALLOC=y
 # CONFIG_MBEDTLS_EXTERNAL_MEM_ALLOC is not set
-CONFIG_MBEDTLS_DEFAULT_MEM_ALLOC=y
+# CONFIG_MBEDTLS_DEFAULT_MEM_ALLOC is not set
 # CONFIG_MBEDTLS_CUSTOM_MEM_ALLOC is not set
 CONFIG_MBEDTLS_ASYMMETRIC_CONTENT_LEN=y
 CONFIG_MBEDTLS_SSL_IN_CONTENT_LEN=16384
@@ -1834,7 +1835,7 @@ CONFIG_STDATOMIC_S32C1I_SPIRAM_WORKAROUND=y
 # CONFIG_NVS_ENCRYPTION is not set
 # CONFIG_NVS_ASSERT_ERROR_CHECK is not set
 # CONFIG_NVS_LEGACY_DUP_KEYS_COMPATIBILITY is not set
-CONFIG_NVS_ALLOCATE_CACHE_IN_SPIRAM=y
+# CONFIG_NVS_ALLOCATE_CACHE_IN_SPIRAM is not set
 # end of NVS
 
 #
@@ -1876,6 +1877,12 @@ CONFIG_SPI_FLASH_BROWNOUT_RESET=y
 #
 # Features here require specific hardware (READ DOCS FIRST!)
 #
+# CONFIG_SPI_FLASH_HPM_ENA is not set
+CONFIG_SPI_FLASH_HPM_AUTO=y
+# CONFIG_SPI_FLASH_HPM_DIS is not set
+CONFIG_SPI_FLASH_HPM_ON=y
+CONFIG_SPI_FLASH_HPM_DC_AUTO=y
+# CONFIG_SPI_FLASH_HPM_DC_DISABLE is not set
 # CONFIG_SPI_FLASH_AUTO_SUSPEND is not set
 CONFIG_SPI_FLASH_SUSPEND_TSUS_VAL_US=50
 # CONFIG_SPI_FLASH_FORCE_ENABLE_XMC_C_SUSPEND is not set
@@ -1890,6 +1897,7 @@ CONFIG_SPI_FLASH_PLACE_FUNCTIONS_IN_IRAM=y
 # CONFIG_SPI_FLASH_VERIFY_WRITE is not set
 # CONFIG_SPI_FLASH_ENABLE_COUNTERS is not set
 CONFIG_SPI_FLASH_ROM_DRIVER_PATCH=y
+# CONFIG_SPI_FLASH_ROM_IMPL is not set
 CONFIG_SPI_FLASH_DANGEROUS_WRITE_ABORTS=y
 # CONFIG_SPI_FLASH_DANGEROUS_WRITE_FAILS is not set
 # CONFIG_SPI_FLASH_DANGEROUS_WRITE_ALLOWED is not set
@@ -2396,8 +2404,11 @@ CONFIG_LOG_BOOTLOADER_LEVEL_INFO=y
 # CONFIG_LOG_BOOTLOADER_LEVEL_DEBUG is not set
 # CONFIG_LOG_BOOTLOADER_LEVEL_VERBOSE is not set
 CONFIG_LOG_BOOTLOADER_LEVEL=3
-CONFIG_SPI_FLASH_OCTAL_32BIT_ADDR_ENABLE=y
 # CONFIG_FLASH_ENCRYPTION_ENABLED is not set
+# CONFIG_FLASHMODE_QIO is not set
+# CONFIG_FLASHMODE_QOUT is not set
+CONFIG_FLASHMODE_DIO=y
+# CONFIG_FLASHMODE_DOUT is not set
 CONFIG_MONITOR_BAUD=115200
 # CONFIG_OPTIMIZATION_LEVEL_DEBUG is not set
 # CONFIG_COMPILER_OPTIMIZATION_LEVEL_DEBUG is not set
@@ -2490,22 +2501,21 @@ CONFIG_ESP32_WIFI_ENABLED=y
 CONFIG_ESP32_WIFI_STATIC_RX_BUFFER_NUM=10
 CONFIG_ESP32_WIFI_DYNAMIC_RX_BUFFER_NUM=32
 CONFIG_ESP32_WIFI_STATIC_TX_BUFFER=y
+# CONFIG_ESP32_WIFI_DYNAMIC_TX_BUFFER is not set
 CONFIG_ESP32_WIFI_TX_BUFFER_TYPE=0
 CONFIG_ESP32_WIFI_STATIC_TX_BUFFER_NUM=16
-CONFIG_ESP32_WIFI_CACHE_TX_BUFFER_NUM=32
 # CONFIG_ESP32_WIFI_CSI_ENABLED is not set
 CONFIG_ESP32_WIFI_AMPDU_TX_ENABLED=y
 CONFIG_ESP32_WIFI_TX_BA_WIN=6
 CONFIG_ESP32_WIFI_AMPDU_RX_ENABLED=y
 CONFIG_ESP32_WIFI_RX_BA_WIN=6
-# CONFIG_ESP32_WIFI_AMSDU_TX_ENABLED is not set
 CONFIG_ESP32_WIFI_NVS_ENABLED=y
 # CONFIG_ESP32_WIFI_TASK_PINNED_TO_CORE_0 is not set
 CONFIG_ESP32_WIFI_TASK_PINNED_TO_CORE_1=y
 CONFIG_ESP32_WIFI_SOFTAP_BEACON_MAX_LEN=752
 CONFIG_ESP32_WIFI_MGMT_SBUF_NUM=32
-# CONFIG_ESP32_WIFI_IRAM_OPT is not set
-# CONFIG_ESP32_WIFI_RX_IRAM_OPT is not set
+CONFIG_ESP32_WIFI_IRAM_OPT=y
+CONFIG_ESP32_WIFI_RX_IRAM_OPT=y
 CONFIG_ESP32_WIFI_ENABLE_WPA3_SAE=y
 CONFIG_ESP32_WIFI_ENABLE_WPA3_OWE_STA=y
 CONFIG_WPA_MBEDTLS_CRYPTO=y