Merge pull request #2815 from UltimateCodeWarrior/fix/tbeam-supreme-v3-oled-i2c

Fix blank OLED on T-Beam Supreme V3 (I2C bus init + 0x3D address)

Author: liamcottle

src/helpers/esp32/TBeamBoard.cpp

@@ -16,6 +16,16 @@ void TBeamBoard::begin() {
 
     ESP32Board::begin();
 
+#ifdef TBEAM_SUPREME_SX1262
+    // On the T-Beam S3 Supreme the PMU + RTC sit on Wire1 (GPIO 42/41, brought
+    // up by XPowersLib), while the SH1106 OLED and the BME280/QMC6310 sensors
+    // sit on the primary bus, Wire (GPIO PIN_BOARD_SDA/PIN_BOARD_SCL). Nothing
+    // else initialises Wire on this board, so the display driver would
+    // otherwise talk on the wrong (default) pins and display.begin() fails,
+    // leaving the screen blank. Bring the OLED bus up here.
+    Wire.begin(PIN_BOARD_SDA, PIN_BOARD_SCL);
+#endif
+
     power_init();
 
     //Configure user button

src/helpers/ui/SH1106Display.cpp

@@ -11,7 +11,10 @@ bool SH1106Display::i2c_probe(TwoWire &wire, uint8_t addr)
 
 bool SH1106Display::begin()
 {
-  return display.begin(DISPLAY_ADDRESS, true) && i2c_probe(Wire, DISPLAY_ADDRESS);
+  // Wire must already be initialised by board.begin() before this is called.
+  // Boards with non-standard SH1106 addresses should define DISPLAY_ADDRESS
+  // in their variant/platformio configuration.
+  return i2c_probe(Wire, DISPLAY_ADDRESS) && display.begin(DISPLAY_ADDRESS, true);
 }
 
 void SH1106Display::turnOn()

variants/lilygo_tbeam_supreme_SX1262/platformio.ini

@@ -18,6 +18,7 @@ build_flags =
   -D RADIO_CLASS=CustomSX1262
   -D WRAPPER_CLASS=CustomSX1262Wrapper
   -D DISPLAY_CLASS=SH1106Display
+  -D DISPLAY_ADDRESS=0x3D
   -D LORA_TX_POWER=22
   -D P_LORA_TX_LED=6
   -D PIN_BOARD_SDA=17