add T-Echo-Lite Device Variant

variants/lilygo_techo_lite/TechoBoard.h

@@ -0,0 +1,55 @@
+#pragma once
+
+#include <MeshCore.h>
+#include <Arduino.h>
+
+// built-ins
+#define VBAT_MV_PER_LSB   (0.73242188F)   // 3.0V ADC range and 12-bit ADC resolution = 3000mV/4096
+
+#define VBAT_DIVIDER      (0.5F)          // 150K + 150K voltage divider on VBAT
+#define VBAT_DIVIDER_COMP (2.0F)          // Compensation factor for the VBAT divider
+
+#define PIN_VBAT_READ     (4)
+#define REAL_VBAT_MV_PER_LSB (VBAT_DIVIDER_COMP * VBAT_MV_PER_LSB)
+
+class TechoBoard : public mesh::MainBoard {
+protected:
+  uint8_t startup_reason;
+
+public:
+
+  void begin();
+  uint16_t getBattMilliVolts() override;
+  bool startOTAUpdate(const char* id, char reply[]) override;
+
+  uint8_t getStartupReason() const override {
+    return startup_reason;
+  }
+
+  const char* getManufacturerName() const override {
+    return "LilyGo T-Echo";
+  }
+
+  void powerOff() override {
+    #ifdef LED_RED
+    digitalWrite(LED_RED, LOW);
+    #endif
+    #ifdef LED_GREEN
+    digitalWrite(LED_GREEN, LOW);
+    #endif
+    #ifdef LED_BLUE
+    digitalWrite(LED_BLUE, LOW);
+    #endif
+    #ifdef DISP_BACKLIGHT
+    digitalWrite(DISP_BACKLIGHT, LOW);
+    #endif
+    #ifdef PIN_PWR_EN
+    digitalWrite(PIN_PWR_EN, LOW);
+    #endif
+    sd_power_system_off();
+  }
+
+  void reboot() override {
+    NVIC_SystemReset();
+  }
+};