Merge pull request #289 from adam2872/RAK4631-user-button

Implement user button on RAK4631 using analogue pin 31 (same as MT)

examples/companion_radio/UITask.cpp

@@ -232,15 +232,23 @@ void UITask::userLedHandler() {
 }
 
 void UITask::buttonHandler() {
-#ifdef PIN_USER_BTN
+  #if defined(PIN_USER_BTN) || defined(PIN_USER_BTN_ANA)
     static int prev_btn_state = !USER_BTN_PRESSED;
+    static int prev_btn_state_ana = !USER_BTN_PRESSED;
     static unsigned long btn_state_change_time = 0;
     static unsigned long next_read = 0;
     int cur_time = millis();
     if (cur_time >= next_read) {
-    int btn_state = digitalRead(PIN_USER_BTN);
-    if (btn_state != prev_btn_state) {
-      if (btn_state == USER_BTN_PRESSED) {  // pressed?
+      int btn_state = 0;
+      int btn_state_ana = 0;
+      #ifdef PIN_USER_BTN
+      btn_state = digitalRead(PIN_USER_BTN);
+      #endif
+      #ifdef PIN_USER_BTN_ANA
+      btn_state_ana = (analogRead(PIN_USER_BTN_ANA) < 20); // analogRead returns a value hopefully below 20 when button is pressed. 
+      #endif
+      if (btn_state != prev_btn_state || btn_state_ana != prev_btn_state_ana) { // check for either digital or analogue button change of state
+        if (btn_state == USER_BTN_PRESSED || btn_state_ana == USER_BTN_PRESSED) {  // pressed?
           if (_display != NULL) {
             if (_display->isOn()) {
               clearMsgPreview();
@@ -261,11 +269,12 @@ void UITask::buttonHandler() {
         }
         btn_state_change_time = millis();
         prev_btn_state = btn_state;
+        prev_btn_state_ana = btn_state_ana;
       }
       next_read = millis() + 100;  // 10 reads per second
     }
-#endif
-}
+  #endif
+  }
 
 void UITask::loop() {
   buttonHandler();

src/helpers/nrf52/RAK4631Board.cpp

@@ -26,6 +26,10 @@ void RAK4631Board::begin() {
   pinMode(PIN_USER_BTN, INPUT_PULLUP);
 #endif
 
+#ifdef PIN_USER_BTN_ANA
+  pinMode(PIN_USER_BTN_ANA, INPUT_PULLUP);
+#endif
+
 #if defined(PIN_BOARD_SDA) && defined(PIN_BOARD_SCL)
   Wire.setPins(PIN_BOARD_SDA, PIN_BOARD_SCL);
 #endif

variants/rak4631/platformio.ini

@@ -7,6 +7,7 @@ build_flags = ${nrf52840_base.build_flags}
   -I variants/rak4631
   -D RAK_4631
   -D PIN_USER_BTN=9
+  -D PIN_USER_BTN_ANA=31
   -D PIN_BOARD_SCL=14
   -D PIN_BOARD_SDA=13
   -D PIN_OLED_RESET=-1