fix: infinite loop of rebooting

heartbeat.rules

@@ -1 +1,2 @@
+# should be in /etc/udev/rules.d/
 ACTION=="add", ATTRS{idProduct}=="7523", ATTRS{idVendor}=="1a86", NAME="watchdog"

mcu-server-watchdog.ino

@@ -1,48 +1,53 @@
-const int HEARTBEAT_REBOOT_DELAY_MILLIS = 20000;  //this is coupled to the HEARTBEAT_INTERVAL in src/main.rs
-const int HEARTBEAT_BOOT_DELAY_MILLIS = 60000;
+const int HEARTBEAT_REBOOT_DELAY_MILLIS = 2000;  //this is coupled to the HEARTBEAT_INTERVAL in src/main.rs
+const int HEARTBEAT_BOOT_DELAY_MILLIS = 9000;
 const int PIN_REBOOT = 2;
 const int PIN_BOOT = 3;
 
+bool rebooted = false;
+
 unsigned long startTimeMillis;
 void setup() {
   Serial.begin(9600);
   pinMode(PIN_REBOOT, OUTPUT);
   pinMode(PIN_BOOT, OUTPUT);
-  waitForSerial();
   //NOTE might want to replace this initialization with a check in the first loop, so we dont instantly reboot
   startTimeMillis = millis(); 
 
 }
 
 void loop(){
-  if (millis() - startTimeMillis > HEARTBEAT_REBOOT_DELAY_MILLIS){pin_switch(PIN_REBOOT);}
   if (Serial.available() > 0) { // if something has been written to the serial port
     startTimeMillis = millis();
     clearSerial();
+    rebooted = false;
+    Serial.println("read serial");
   }
+  unsigned long timeElapsed = millis() - startTimeMillis;
+  if (timeElapsed > HEARTBEAT_REBOOT_DELAY_MILLIS &&  not rebooted){
+    pin_switch(PIN_REBOOT);
+    startTimeMillis = millis();
+    rebooted = true;
+    Serial.println("reboot");
+
+  }
+  if (timeElapsed > HEARTBEAT_BOOT_DELAY_MILLIS){
+    pin_switch(PIN_BOOT);
+    startTimeMillis = millis();
+    Serial.println("boot");
+
+  }
+  
 }
 
 
 void pin_switch(int pin){
   //TODO connect the RST pins on the motherboard
-  Serial.println("Error!");
   digitalWrite(pin, LOW);
   delay(500);
   digitalWrite(pin, HIGH);
-  waitForSerial();
 }
 
-/*
-busy wait for first serial input
-*/
-void waitForSerial(){
-    while(Serial.available() == 0){
-    //check if we may need to initiate a normal boot instead of a reboot, e.g. after a power outage
-    if (millis() - startTimeMillis > HEARTBEAT_BOOT_DELAY_MILLIS){
-      pin_switch(PIN_BOOT);
-    }
-    }
-}
+
 
 void clearSerial(){
   while (Serial.available()>0){