initial support for Seeed Studio SenseCap Solar board

variants/sensecap_solar/SenseCapSolarBoard.h

@@ -0,0 +1,42 @@
+#pragma once
+
+#include <MeshCore.h>
+#include <Arduino.h>
+
+class SenseCapSolarBoard : public mesh::MainBoard {
+protected:
+  uint8_t startup_reason;
+
+public:
+  void begin();
+  uint8_t getStartupReason() const override { return startup_reason; }
+
+#if defined(P_LORA_TX_LED)
+  void onBeforeTransmit() override {
+    digitalWrite(P_LORA_TX_LED, LOW);   // turn TX LED on
+  }
+  void onAfterTransmit() override {
+    digitalWrite(P_LORA_TX_LED, HIGH);   // turn TX LED off
+  }
+#endif
+
+  uint16_t getBattMilliVolts() override {
+    digitalWrite(VBAT_ENABLE, LOW);
+    int adcvalue = 0;
+    analogReadResolution(12);
+    analogReference(AR_INTERNAL_3_0);
+    delay(10);
+    adcvalue = analogRead(BATTERY_PIN);
+    return (adcvalue * ADC_MULTIPLIER * AREF_VOLTAGE) / 4.096;
+  }
+
+  const char* getManufacturerName() const override {
+    return "Seeed SenseCap Solar";
+  }
+
+  void reboot() override {
+    NVIC_SystemReset();
+  }
+
+  bool startOTAUpdate(const char* id, char reply[]) override;
+};