* new helper: AutoDiscoverRTCClock, which detects: DS3231 (on i2c addr 0x68), or RV3028 (on i2c addr 0x52)

* repeater and room server: ver bump (v5), now use AutoDiscoverRTCClock
* various Board::begin() now should do Wire.begin(), with custom pin mappings if needed
* examples removed: ping client/server, and test_admin

src/helpers/AutoDiscoverRTCClock.cpp

@@ -0,0 +1,61 @@
+#include "AutoDiscoverRTCClock.h"
+#include "RTClib.h"
+#include <Melopero_RV3028.h>
+
+static RTC_DS3231 rtc_3231;
+static bool ds3231_success = false;
+
+static Melopero_RV3028 rtc_rv3028;
+static bool rv3028_success = false;
+
+#define DS3231_ADDRESS   0x68
+#define RV3028_ADDRESS   0x52
+
+bool AutoDiscoverRTCClock::i2c_probe(TwoWire& wire, uint8_t addr) {
+  wire.beginTransmission(addr);
+  uint8_t error = wire.endTransmission();
+  return (error == 0);
+}
+
+void AutoDiscoverRTCClock::begin(TwoWire& wire) {
+  if (i2c_probe(wire, DS3231_ADDRESS)) {
+    ds3231_success = rtc_3231.begin(&wire);
+  }
+  if (i2c_probe(wire, RV3028_ADDRESS)) {
+    rtc_rv3028.initI2C(wire);
+	rtc_rv3028.writeToRegister(0x35, 0x00);
+	rtc_rv3028.writeToRegister(0x37, 0xB4); // Direct Switching Mode (DSM): when VDD < VBACKUP, switchover occurs from VDD to VBACKUP
+	rtc_rv3028.set24HourMode(); // Set the device to use the 24hour format (default) instead of the 12 hour format
+    rv3028_success = true;
+  }
+}
+
+uint32_t AutoDiscoverRTCClock::getCurrentTime() {
+  if (ds3231_success) {
+    return rtc_3231.now().unixtime();
+  }
+  if (rv3028_success) {
+    return DateTime(
+        rtc_rv3028.getYear(),
+        rtc_rv3028.getMonth(),
+        rtc_rv3028.getDate(),
+        rtc_rv3028.getHour(),
+        rtc_rv3028.getMinute(),
+        rtc_rv3028.getSecond()
+    ).unixtime();
+  }
+  return _fallback->getCurrentTime();
+}
+
+void AutoDiscoverRTCClock::setCurrentTime(uint32_t time) { 
+  if (ds3231_success) {
+    rtc_3231.adjust(DateTime(time));
+  } else if (rv3028_success) {
+    auto dt = DateTime(time);
+	uint8_t weekday = (dt.day() + (uint16_t)((2.6 * dt.month()) - 0.2) - (2 * (dt.year() / 100)) + dt.year() + (uint16_t)(dt.year() / 4) + (uint16_t)(dt.year() / 400)) % 7;
+	
+    rtc_rv3028.setTime(dt.year(), dt.month(), weekday, dt.day(), dt.hour(), dt.minute(), dt.second());
+  } else {
+    _fallback->setCurrentTime(time);
+  }
+}

src/helpers/AutoDiscoverRTCClock.h

@@ -0,0 +1,17 @@
+#pragma once
+
+#include <Mesh.h>
+#include <Arduino.h>
+#include <Wire.h>
+
+class AutoDiscoverRTCClock : public mesh::RTCClock {
+  mesh::RTCClock* _fallback;
+
+  bool i2c_probe(TwoWire& wire, uint8_t addr);
+public:
+  AutoDiscoverRTCClock(mesh::RTCClock& fallback) : _fallback(&fallback) { }
+
+  void begin(TwoWire& wire);
+  uint32_t getCurrentTime() override;
+  void setCurrentTime(uint32_t time) override;
+};

src/helpers/ESP32Board.h

@@ -27,6 +27,12 @@ public:
     pinMode(P_LORA_TX_LED, OUTPUT);
     digitalWrite(P_LORA_TX_LED, LOW);
   #endif
+
+  #if defined(PIN_BOARD_SDA) && defined(PIN_BOARD_SCL)
+    Wire.begin(PIN_BOARD_SDA, PIN_BOARD_SCL);
+  #else
+    Wire.begin();
+  #endif
   }
 
   uint8_t getStartupReason() const override { return startup_reason; }

src/helpers/nrf52/RAK4631Board.cpp

@@ -20,6 +20,23 @@ static void disconnect_callback(uint16_t conn_handle, uint8_t reason)
     MESH_DEBUG_PRINTLN("BLE client disconnected");
 }
 
+void RAK4631Board::begin() {
+  // for future use, sub-classes SHOULD call this from their begin()
+  startup_reason = BD_STARTUP_NORMAL;
+
+  pinMode(PIN_VBAT_READ, INPUT);
+
+#if defined(PIN_BOARD_SDA) && defined(PIN_BOARD_SCL)
+  Wire.begin(PIN_BOARD_SDA, PIN_BOARD_SCL);
+#else
+  Wire.begin();
+#endif
+
+  pinMode(SX126X_POWER_EN, OUTPUT);
+  digitalWrite(SX126X_POWER_EN, HIGH);
+  delay(10);   // give sx1262 some time to power up
+}
+
 bool RAK4631Board::startOTAUpdate() {
     // Config the peripheral connection with maximum bandwidth
     // more SRAM required by SoftDevice

src/helpers/nrf52/RAK4631Board.h

@@ -25,17 +25,7 @@ protected:
   uint8_t startup_reason;
 
 public:
-  void begin() {
-    // for future use, sub-classes SHOULD call this from their begin()
-    startup_reason = BD_STARTUP_NORMAL;
-
-    pinMode(PIN_VBAT_READ, INPUT);
-
-    pinMode(SX126X_POWER_EN, OUTPUT);
-    digitalWrite(SX126X_POWER_EN, HIGH);
-    delay(10);   // give sx1262 some time to power up
-  }
-
+  void begin();
   uint8_t getStartupReason() const override { return startup_reason; }
 
   #define BATTERY_SAMPLES 8

src/helpers/nrf52/T1000eBoard.cpp

@@ -4,7 +4,23 @@
 #include <bluefruit.h>
 #include <Wire.h>
 
+void T1000eBoard::begin() {
+  // for future use, sub-classes SHOULD call this from their begin()
+  startup_reason = BD_STARTUP_NORMAL;
 
+#if defined(PIN_BOARD_SDA) && defined(PIN_BOARD_SCL)
+  Wire.begin(PIN_BOARD_SDA, PIN_BOARD_SCL);
+#else
+  Wire.begin();
+#endif
+
+  //    pinMode(PIN_VBAT_READ, INPUT);
+
+  // Doesn't seem to be a pwr en pin ...
+  //    pinMode(LR1110_POWER_EN, OUTPUT);
+  //    digitalWrite(LR1110_POWER_EN, HIGH);
+    delay(10);   // give sx1262 some time to power up
+}
 
 #if 0
 static BLEDfu bledfu;

src/helpers/nrf52/T1000eBoard.h

@@ -25,17 +25,7 @@ protected:
   uint8_t startup_reason;
 
 public:
-  void begin() {
-    // for future use, sub-classes SHOULD call this from their begin()
-    startup_reason = BD_STARTUP_NORMAL;
-
-//    pinMode(PIN_VBAT_READ, INPUT);
-
-// Doesn't seem to be a pwr en pin ...
-//    pinMode(LR1110_POWER_EN, OUTPUT);
-//    digitalWrite(LR1110_POWER_EN, HIGH);
-    delay(10);   // give sx1262 some time to power up
-  }
+  void begin();
 
   uint16_t getBattMilliVolts() override {
     return 0;