Detect modem communication timeouts for sx126x chips

sx126x.cpp

@@ -485,21 +485,30 @@ int sx126x::endPacket()
 
   executeOpcodeRead(OP_GET_IRQ_STATUS_6X, buf, 2);
 
+  bool timed_out = false;
+  uint32_t w_timeout = millis()+LORA_MODEM_TIMEOUT_MS;
   // wait for TX done
-      while ((buf[1] & IRQ_TX_DONE_MASK_6X) == 0) {
+  while ((millis() < w_timeout) && ((buf[1] & IRQ_TX_DONE_MASK_6X) == 0)) {
     buf[0] = 0x00;
     buf[1] = 0x00;
     executeOpcodeRead(OP_GET_IRQ_STATUS_6X, buf, 2);
     yield();
   }
 
+  if (!(millis() < w_timeout)) { timed_out = true; }
+
   // clear IRQ's
 
   uint8_t mask[2];
   mask[0] = 0x00;
   mask[1] = IRQ_TX_DONE_MASK_6X;
   executeOpcode(OP_CLEAR_IRQ_STATUS_6X, mask, 2);
+  
+  if (timed_out) {
+    return 0;
+  } else {
     return 1;
+  }
 }
 
 uint8_t sx126x::modemStatus() {

sx126x.h

@@ -17,6 +17,7 @@
 #define LORA_DEFAULT_RXEN_PIN  -1
 #define LORA_DEFAULT_TXEN_PIN  -1
 #define LORA_DEFAULT_BUSY_PIN  -1
+#define LORA_MODEM_TIMEOUT_MS 20E3
 
 #define PA_OUTPUT_RFO_PIN      0
 #define PA_OUTPUT_PA_BOOST_PIN 1