Initial commit: RNodeTHV4 boundary mode firmware for Heltec V4

Bridges LoRa mesh and TCP/WiFi backbone networks using microReticulum.
Based on microReticulum_Firmware with boundary mode additions:
- BoundaryMode.h: State management and EEPROM persistence
- BoundaryConfig.h: WiFi captive portal for configuration
- TcpInterface.h: TCP backbone interface with HDLC framing
- Display.h: Custom OLED layout with network status indicators
- Transport/Identity library patches for embedded memory constraints

variants/rak3112/pins_arduino.h

@@ -0,0 +1,97 @@
+#ifndef Pins_Arduino_h
+#define Pins_Arduino_h
+
+#include <stdint.h>
+
+#ifndef _VARIANT_RAK3112_
+#define _VARIANT_RAK3112_
+#endif
+
+#define USB_VID 0x303a
+#define USB_PID 0x1001
+
+// GPIO's
+#define WB_IO1 21
+#define WB_IO2 2
+// #define WB_IO2 14
+#define WB_IO3 41
+#define WB_IO4 42
+#define WB_IO5 38
+#define WB_IO6 39
+// #define WB_SW1 35 NC
+#define WB_A0 1
+#define WB_A1 2
+#define WB_CS 12
+#define WB_LED1 46
+#define WB_LED2 45
+
+// LEDs
+#define PIN_LED1 (46)
+#define PIN_LED2 (45)
+#define LED_BLUE PIN_LED2
+#define LED_GREEN PIN_LED1
+#define LED_BUILTIN LED_GREEN
+#define LED_CONN PIN_LED2
+#define LED_STATE_ON 1 // State when LED is litted
+
+/*
+ * Analog pins
+ */
+#define PIN_A0 (21)
+#define PIN_A1 (14)
+
+/*
+ * Serial interfaces
+ */
+// TXD1 RXD1 on Base Board
+#define PIN_SERIAL1_RX (44)
+#define PIN_SERIAL1_TX (43)
+
+// TXD0 RXD0 on Base Board (NC due to large flash chip)
+// #define PIN_SERIAL2_RX (19)
+// #define PIN_SERIAL2_TX (20)
+
+/*
+ * SPI Interfaces
+ */
+#define SPI_INTERFACES_COUNT 1
+
+#define PIN_SPI_MISO (10)
+#define PIN_SPI_MOSI (11)
+#define PIN_SPI_SCK (13)
+#define SPI_CS (12)
+
+static const uint8_t SS = SPI_CS;
+static const uint8_t MOSI = PIN_SPI_MOSI;
+static const uint8_t MISO = PIN_SPI_MISO;
+static const uint8_t SCK = PIN_SPI_SCK;
+
+// Internal SPI to LoRa transceiver
+#define LORA_SX126X_SCK 5
+#define LORA_SX126X_MISO 3
+#define LORA_SX126X_MOSI 6
+#define LORA_SX126X_CS 7
+#define LORA_SX126X_RESET 8
+#define LORA_SX126X_DIO1 47
+#define LORA_SX126X_BUSY 48
+#define LORA_SX126X_DIO2_AS_RF_SWITCH 1
+#define LORA_SX126X_DIO3_TCXO_VOLTAGE 1.8
+
+/*
+ * Wire Interfaces
+ */
+#define WIRE_INTERFACES_COUNT 2
+
+#ifndef PIN_WIRE_SDA
+#define PIN_WIRE_SDA (9)
+#endif
+#ifndef PIN_WIRE_SCL
+#define PIN_WIRE_SCL (40)
+#endif
+#define SDA PIN_WIRE_SDA
+#define SCL PIN_WIRE_SCL
+
+#define PIN_WIRE1_SDA (17)
+#define PIN_WIRE1_SCL (18)
+
+#endif /* Pins_Arduino_h */