feat: add M5Stack Unit C6L variant support

src/helpers/esp32/SerialBLEInterface.cpp

@@ -1,5 +1,5 @@
 #include "SerialBLEInterface.h"
-#include "esp_mac.h"
+#include <esp_mac.h>
 
 // See the following for generating UUIDs:
 // https://www.uuidgenerator.net/

src/helpers/ui/DisplayDriver.h

@@ -3,21 +3,72 @@
 #include <stdint.h>
 #include <string.h>
 
+// MarqueeScroller: Handles text scrolling for small displays (e.g., 64x48 OLED)
+// Used by companion radio UI to display long messages that don't fit on screen
+struct MarqueeScroller {
+  int offset = 0;              // Current scroll offset in pixels
+  unsigned long next_time = 0; // Next scroll update time (millis)
+  bool paused = true;          // Scroll paused state
+
+  // Reset scroller to initial state
+  void reset() {
+    offset = 0;
+    next_time = 0;
+    paused = true;
+  }
+
+  // Update scroll position - call once per loop iteration
+  // Parameters:
+  //   textW - width of text in pixels
+  //   displayW - width of display in pixels
+  //   now - current time from millis()
+  //   speed_ms - milliseconds between scroll steps (default: 150ms)
+  //   pause_ms - milliseconds to pause before scrolling starts (default: 2000ms)
+  void update(int textW, int displayW, unsigned long now,
+              unsigned long speed_ms = 150, unsigned long pause_ms = 2000) {
+    int maxScroll = textW - displayW;
+    if (maxScroll <= 0) { offset = 0; return; }
+    if (now < next_time) return;
+    if (paused) {
+      paused = false;
+      next_time = now + pause_ms;
+    } else {
+      offset++;
+      if (offset >= maxScroll) {
+        offset = 0;
+        paused = true;
+      }
+      next_time = now + speed_ms;
+    }
+  }
+};
+
+// UIColor framework: Provides consistent color definitions across different display types
+// Each display driver defines its own UIColor values based on its color capabilities
+// For monochrome displays: 0 = BLACK, 1 = WHITE
+// For color displays: 16-bit RGB values
 using ColorVal = uint16_t;
 
 class UIColor {
 public:
-  // color definitions (by element _type_)
-  static ColorVal window_bkg, title_bkg, title_txt, primary_txt, secondary_txt, warning_txt, popup_bkg, popup_txt, corp_blue;
+  // UI element color definitions
+  // Each display driver implements these with appropriate values for its display
+  static ColorVal window_bkg;      // Background color for windows/panels
+  static ColorVal title_bkg;       // Background color for title bars
+  static ColorVal title_txt;       // Text color for titles
+  static ColorVal primary_txt;     // Primary text color (main content)
+  static ColorVal secondary_txt;   // Secondary text color (metadata, timestamps)
+  static ColorVal warning_txt;     // Warning/alert text color
+  static ColorVal popup_bkg;       // Background color for popups/dialogs
+  static ColorVal popup_txt;       // Text color for popups/dialogs
+  static ColorVal corp_blue;       // Corporate/brand color (blue)
 };
 
 class DisplayDriver {
   int _w, _h;
 protected:
   DisplayDriver(int w, int h) { _w = w; _h = h; }
 public:
-  //enum Color { DARK=0, LIGHT, RED, GREEN, BLUE, YELLOW, ORANGE }; // on b/w screen, colors will be !=0 synonym of light
-
   int width() const { return _w; }
   int height() const { return _h; }
 
@@ -59,7 +110,7 @@ class DisplayDriver {
       if (c >= 32 && c <= 126) {
         dest[j++] = c;  // ASCII printable
       } else if (c >= 0x80) {
-        dest[j++] = '\xDB';  // CP437 full block █
+        dest[j++] = '\xDB';  // CP437 full block �
         while (src[i+1] && (src[i+1] & 0xC0) == 0x80) 
           i++;  // skip UTF-8 continuation bytes
       }
@@ -106,4 +157,4 @@ class DisplayDriver {
   }
 
   virtual void endFrame() = 0;
-};
+};

src/helpers/ui/SSD1306SPIDisplay.cpp

@@ -0,0 +1,131 @@
+#include "SSD1306SPIDisplay.h"
+
+// UIColor definitions for 64x48 OLED (black/white display)
+ColorVal UIColor::window_bkg = 0;       // BLACK
+ColorVal UIColor::title_bkg = 0;        // BLACK
+ColorVal UIColor::title_txt = 1;        // WHITE
+ColorVal UIColor::primary_txt = 1;      // WHITE
+ColorVal UIColor::secondary_txt = 1;    // WHITE
+ColorVal UIColor::warning_txt = 1;      // WHITE
+ColorVal UIColor::popup_bkg = 0;        // BLACK
+ColorVal UIColor::popup_txt = 1;        // WHITE
+ColorVal UIColor::corp_blue = 1;        // WHITE (B/W display)
+
+// Check if SPI is ready (set by radio_init in target.cpp)
+#if defined(P_LORA_SCLK)
+  extern bool spi_initialized;
+#else
+  static bool spi_initialized = true;  // Assume ready if no custom SPI
+#endif
+
+bool SSD1306SPIDisplay::begin() {
+  // Defer actual initialization - SPI may not be ready yet
+  // Real init happens in lazyInit() on first use (after radio_init)
+  return true;
+}
+
+bool SSD1306SPIDisplay::lazyInit() {
+  if (_initialized) return true;
+  if (!spi_initialized) {
+    Serial.println("SSD1306: SPI not initialized yet");
+    return false;
+  }
+
+  Serial.println("SSD1306: Attempting display init...");
+  #ifdef DISPLAY_ROTATION
+  display.setRotation(DISPLAY_ROTATION);
+  #endif
+  // SPI is now initialized by radio_init()
+  // Pass periphBegin=false to skip spi.begin() since radio already did it
+  if (!display.begin(SSD1306_SWITCHCAPVCC, 0, true, false)) {
+    Serial.println("SSD1306: display.begin() FAILED");
+    return false;
+  }
+  Serial.println("SSD1306: display.begin() OK");
+
+  // Fix for 64x48 displays: Adafruit library lacks this case and defaults
+  // to comPins=0x02 (sequential). Displays taller than 32px need 0x12
+  // (alternative COM pin config) or the output is garbled.
+  #if defined(DISPLAY_WIDTH) && defined(DISPLAY_HEIGHT)
+  #if (DISPLAY_WIDTH == 64) && (DISPLAY_HEIGHT == 48)
+  display.ssd1306_command(SSD1306_SETCOMPINS);
+  display.ssd1306_command(0x12);
+  #endif
+  #endif
+
+  // Clear any garbage in the display buffer
+  display.clearDisplay();
+  display.display();
+  _initialized = true;
+  return true;
+}
+
+void SSD1306SPIDisplay::turnOn() {
+  if (!lazyInit()) return;
+  display.ssd1306_command(SSD1306_DISPLAYON);
+  _isOn = true;
+}
+
+void SSD1306SPIDisplay::turnOff() {
+  if (!lazyInit()) return;
+  display.ssd1306_command(SSD1306_DISPLAYOFF);
+  _isOn = false;
+}
+
+void SSD1306SPIDisplay::clear() {
+  if (!lazyInit()) return;
+  display.clearDisplay();
+  display.display();
+}
+
+void SSD1306SPIDisplay::startFrame(ColorVal bkg) {
+  if (!lazyInit()) return;
+  display.clearDisplay();  // TODO: apply 'bkg'
+  _color = 1;  // WHITE
+  display.setTextColor(_color);
+  display.setFont(NULL);  // Default 6x8 font
+  display.setTextSize(1);
+  display.setTextWrap(false);
+  display.cp437(true);
+}
+
+void SSD1306SPIDisplay::setTextSize(int sz) {
+  display.setTextSize(sz);
+}
+
+void SSD1306SPIDisplay::setColor(ColorVal c) {
+  _color = (c != 0) ? 1 : 0;  // WHITE or BLACK
+  display.setTextColor(_color);
+}
+
+void SSD1306SPIDisplay::setCursor(int x, int y) {
+  display.setCursor(x, y);
+}
+
+void SSD1306SPIDisplay::print(const char* str) {
+  display.print(str);
+}
+
+void SSD1306SPIDisplay::fillRect(int x, int y, int w, int h) {
+  display.fillRect(x, y, w, h, _color);
+}
+
+void SSD1306SPIDisplay::drawRect(int x, int y, int w, int h) {
+  display.drawRect(x, y, w, h, _color);
+}
+
+void SSD1306SPIDisplay::drawXbm(int x, int y, const uint8_t* bits, int w, int h) {
+  display.drawBitmap(x, y, bits, w, h, SSD1306_WHITE);
+}
+
+uint16_t SSD1306SPIDisplay::getTextWidth(const char* str) {
+  int16_t x1, y1;
+  uint16_t w, h;
+  display.getTextBounds(str, 0, 0, &x1, &y1, &w, &h);
+  return w;
+}
+
+void SSD1306SPIDisplay::endFrame() {
+  if (!_initialized) return;
+  display.display();
+}

src/helpers/ui/SSD1306SPIDisplay.h

@@ -0,0 +1,38 @@
+#pragma once
+
+#include "DisplayDriver.h"
+#include <SPI.h>
+#include <Adafruit_GFX.h>
+#define SSD1306_NO_SPLASH
+#include <Adafruit_SSD1306.h>
+
+class SSD1306SPIDisplay : public DisplayDriver {
+  Adafruit_SSD1306 display;
+  bool _isOn;
+  bool _initialized;
+  uint8_t _color;
+
+  bool lazyInit();  // Deferred init for SPI bus sharing
+
+public:
+  // Accept pre-initialized SPI - do NOT call spi.begin()
+  SSD1306SPIDisplay(SPIClass* spi, int16_t w, int16_t h, int8_t dc, int8_t rst, int8_t cs)
+    : DisplayDriver(w, h), display(w, h, spi, dc, rst, cs) { _isOn = false; _initialized = false; }
+
+  bool begin();
+
+  bool isOn() override { return _isOn; }
+  void turnOn() override;
+  void turnOff() override;
+  void clear() override;
+  void startFrame(ColorVal bkg = UIColor::window_bkg) override;
+  void setTextSize(int sz) override;
+  void setColor(ColorVal c) override;
+  void setCursor(int x, int y) override;
+  void print(const char* str) override;
+  void fillRect(int x, int y, int w, int h) override;
+  void drawRect(int x, int y, int w, int h) override;
+  void drawXbm(int x, int y, const uint8_t* bits, int w, int h) override;
+  uint16_t getTextWidth(const char* str) override;
+  void endFrame() override;
+};

variants/m5stack_unit_c6l/README.md

@@ -0,0 +1,54 @@
+# M5Stack Unit C6L - MeshCore Variant
+
+## Overview
+
+Compact ESP32-C6 LoRa module with integrated SX1262 radio, 64x48 OLED display, and PI4IO I/O expander.
+
+## Hardware
+
+- **MCU:** ESP32-C6 (WiFi 6 + Bluetooth 5 LE)
+- **LoRa:** SX1262 (SPI)
+- **Display:** 64x48 SSD1306 OLED (SPI)
+- **I/O Expander:** PI4IO (I2C)
+- **LED:** NeoPixel (GPIO 2)
+- **Buzzer:** GPIO 11
+
+## Pin Configuration
+
+| Function | GPIO |
+|----------|------|
+| LoRa SCLK | 20 |
+| LoRa MISO | 22 |
+| LoRa MOSI | 21 |
+| LoRa NSS | 23 |
+| LoRa DIO1 | 7 |
+| Display CS | 6 |
+| Display DC | 18 |
+| Display RST | 15 |
+| I2C SDA | 10 |
+| I2C SCL | 8 |
+| NeoPixel | 2 |
+| Buzzer | 11 |
+| GPS RX | 4 |
+| GPS TX | 5 |
+
+## Firmware Environments
+
+| Environment | Interface | Use Case |
+|-------------|-----------|----------|
+| `m5stack_unit_c6l_companion_radio_usb` | USB Serial | Connect via USB |
+| `m5stack_unit_c6l_companion_radio_ble` | BLE | Connect via Bluetooth |
+| `m5stack_unit_c6l_repeater` | LoRa | Network extender |
+| `m5stack_unit_c6l_room_server` | LoRa | BBS server |
+| `m5stack_unit_c6l_kiss_modem` | USB Serial | KISS TNC |
+
+## Build
+
+```bash
+pio run -e m5stack_unit_c6l_companion_radio_usb
+```
+
+## Resources
+
+- [M5Stack Unit C6L Product Page](https://docs.m5stack.com/en/unit/Unit_C6L)
+- [MeshCore Documentation](https://docs.meshcore.io)

variants/m5stack_unit_c6l/UnitC6LBoard.cpp

@@ -4,7 +4,8 @@
 UnitC6LBoard board;
 
 #if defined(P_LORA_SCLK)
-  static SPIClass spi(0);
+  SPIClass spi(0);
+  bool spi_initialized = false;
   RADIO_CLASS radio = new Module(P_LORA_NSS, P_LORA_DIO_1, P_LORA_RESET, P_LORA_BUSY, spi);
 #else
   RADIO_CLASS radio = new Module(P_LORA_NSS, P_LORA_DIO_1, P_LORA_RESET, P_LORA_BUSY);
@@ -16,12 +17,17 @@ ESP32RTCClock fallback_clock;
 AutoDiscoverRTCClock rtc_clock(fallback_clock);
 SensorManager sensors;
 
+#ifdef DISPLAY_CLASS
+  DISPLAY_CLASS display(&spi, DISPLAY_WIDTH, DISPLAY_HEIGHT, DISPLAY_DC, DISPLAY_RST, DISPLAY_CS);
+#endif
+
 bool radio_init() {
   fallback_clock.begin();
   rtc_clock.begin(Wire);
 
 #if defined(P_LORA_SCLK)
   spi.begin(P_LORA_SCLK, P_LORA_MISO, P_LORA_MOSI);
+  spi_initialized = true;
   return radio.std_init(&spi);
 #else
   return radio.std_init();
@@ -30,6 +36,5 @@ bool radio_init() {
 
 mesh::LocalIdentity radio_new_identity() {
   RadioNoiseListener rng(radio);
-  return mesh::LocalIdentity(&rng);  // create new random identity
+  return mesh::LocalIdentity(&rng);
 }
-