Implement TX Retry

firmware/lib/SiedleClient/SiedleClient.cpp

@@ -116,6 +116,7 @@ void SiedleClient::bitTimerISR() {
                 if (bitNumber-- < -3) {
                     // timeout
                     done = true;
+                    txError = true;
                 } else {
                     auto voltage = getBusvoltage();
                     if (voltage >= ADC_CARRIER_HIGH_THRESHOLD_VOLTAGE) {
@@ -193,6 +194,7 @@ void SiedleClient::sendCmdAsync(siedle_cmd_t tx_cmd) {
     cmd_tx_buf = tx_cmd;
     state = transmitting;
     bitNumber = 31;
+    txError = false;
 
     // Output the first bit (#31). Remaining bits will be transmitted using the ISR
     auto bit = bitRead(cmd_tx_buf, bitNumber--);

firmware/lib/SiedleClient/SiedleClient.h

@@ -55,6 +55,9 @@ class SiedleClient {
         return cmd;
     }
 
+    // last transmit was not successful
+    bool txError = false;
+
 private:
     int readBit();
     uint8_t inputPin;

firmware/src/siedle-service.cpp

@@ -33,13 +33,29 @@ void SiedleServiceClass::loop() {
 
     noInterrupts();
     auto now = millis();
-    auto doSend = !siedleTxQueue.isEmpty()
+
+    if (siedleClient.state == idle) {
+        if (siedleClient.txError) {
+            if (retryCounter == -1) {   
+                retryCounter = 3;   
+            }   
+        } else {
+            retryCounter = -1;
+        }
+    }
+
+    auto doSend = (!siedleTxQueue.isEmpty() || retryCounter > 0) 
         && (now - lastTxMillis > BUS_MAX_SEND_RATE_MS)
         && siedleClient.state == idle;
     siedle_cmd_t cmd;
 
     if (doSend) {
-        cmd = siedleTxQueue.pop();
+        if (retryCounter > 0) {
+            retryCounter--;
+            cmd = lastTxCmd;
+        } else {
+            cmd = siedleTxQueue.pop();            
+        }
         siedleClient.sendCmdAsync(cmd);
         lastTxCmd = cmd;
     }

firmware/src/siedle-service.h

@@ -48,6 +48,7 @@ class SiedleServiceClass {
     unsigned long lastTxMillis;
     unsigned int lastTxCounter;
     siedle_cmd_t lastTxCmd;
+    int retryCounter = -1;
 };
 
 extern SiedleServiceClass SiedleService;