rearranged order of hardware initialization

Platformio/hardware/ESP32/hardware_general_hal_esp32.cpp

@@ -2,21 +2,15 @@
 #include <Wire.h>
 #include "tft_hal_esp32.h"
 
-uint8_t SDA_GPIO = 19;
-uint8_t SCL_GPIO = 22;
-
 void init_hardware_general_HAL(void) {
   // Make sure ESP32 is running at full speed
   setCpuFrequencyMhz(240);
 
-  // For I2C to work correctly, the tft has to be powered.
-  // Otherwise the IMU cannot be initialized.
-  // The tft touch controller, being on the same I2C bus, seems to disturb if not powered.
+  // this is power for the TFT IC
   pinMode(LCD_EN_GPIO, OUTPUT);
-  digitalWrite(LCD_EN_GPIO, LOW);
-
-  // SDA and SCL need to be set explicitly, because for IMU you cannot set it explicitly in the constructor.
-  // Configure i2c pins and set frequency to 400kHz
-  Wire.begin(SDA_GPIO, SCL_GPIO, 400000);
+  digitalWrite(LCD_EN_GPIO, HIGH);
+  // this is power for backlight LEDs
+  pinMode(LCD_BL_GPIO, OUTPUT);
+  digitalWrite(LCD_BL_GPIO, HIGH);
 
 }

Platformio/hardware/ESP32/tft_hal_esp32.cpp

@@ -3,6 +3,9 @@
 #include "tft_hal_esp32.h"
 #include "sleep_hal_esp32.h"
 
+uint8_t SDA_GPIO = 19;
+uint8_t SCL_GPIO = 22;
+
 uint8_t LCD_BL_GPIO = 4;
 uint8_t LCD_EN_GPIO = 10;
 
@@ -12,13 +15,6 @@ TS_Point touchPoint;
 byte backlightBrightness = 255;
 
 void init_tft(void) {
-  // this is power for the TFT IC
-  pinMode(LCD_EN_GPIO, OUTPUT);
-  digitalWrite(LCD_EN_GPIO, HIGH);
-  // this is power for backlight LEDs
-  pinMode(LCD_BL_GPIO, OUTPUT);
-  digitalWrite(LCD_BL_GPIO, HIGH);
-
   // Configure the backlight PWM
   // Manual setup because ledcSetup() briefly turns on the backlight
   ledc_channel_config_t ledc_channel_left;
@@ -72,6 +68,9 @@ void init_tft(void) {
   tft.fillScreen(TFT_BLACK);
   tft.setSwapBytes(true);
 
+  // SDA and SCL need to be set explicitly, because for IMU you cannot set it explicitly in the constructor.
+  // Configure i2c pins and set frequency to 400kHz
+  Wire.begin(SDA_GPIO, SCL_GPIO, 400000);
   // Setup touchscreen
   touch.begin(128); // Initialize touchscreen and set sensitivity threshold
 }

Platformio/src/main.cpp

@@ -47,16 +47,14 @@ int main(int argc, char *argv[]) {
   Serial.begin(115200);
   // do some general hardware setup, like powering the TFT, I2C, ...
   init_hardware_general();
+  // get wakeup reason
+  init_sleep();
   // Restore settings from internal flash memory
   init_preferences();
   // blinking led
   init_userled();
   // Power Pin definition
   init_battery();
-  // get wakeup reason
-  init_sleep();
-  // setup the Inertial Measurement Unit (IMU) for motion detection
-  init_IMU();
 
   // button Pin definition for hardware keys
   init_keys();
@@ -90,6 +88,8 @@ int main(int argc, char *argv[]) {
   // init GUI - will initialize tft, touch and lvgl
   init_gui();
   gui_loop(); // Run the LVGL UI once before the loop takes over
+  // setup the Inertial Measurement Unit (IMU) for motion detection. Has to be after init_gui(), otherwise I2C will not work
+  init_IMU();
 
   // register the scenes and their key_commands_*
   register_scene_defaultKeys();