Working firmware

firmware/reflow/reflow.ino

@@ -1,15 +1,15 @@
 /*
- * 60W PD Powered Automatic Reflow Hoteplate
- * Author: tobychui
- * 
- * Notes: 
- * Temperature sensing is done using 1k 1% resistor and a 10k Thermistor
- * You might need to change the code if you are using other values
- * 
- * Touch Button Mappings
- * Start Btn: P1.4
- * Stop Btn: P1.7
- */
+   60W PD Powered Automatic Reflow Hoteplate
+   Author: tobychui
+
+   Notes:
+   Temperature sensing is done using 1k 1% resistor and a 10k Thermistor
+   You might need to change the code if you are using other values
+
+   Touch Button Mappings
+   Start Btn: P1.4
+   Stop Btn: P1.7
+*/
 #include <TouchKey.h>
 
 #define TEMP_PIN 11 //P1.1
@@ -18,19 +18,30 @@
 #define LED_REFLOW 16 //P1.6
 
 //Timing settings. Each cycle is approximately 100ms
-#define HOLDSTART_TIME 100 //START Button hold down time in cycles
-#define SOAKING_TIME 6000 //SOAKING temperature upkeep time in cycles
+#define HOLDSTART_TIME 30 //START Button hold down time in cycles
+#define SOAKING_TIME 600 //SOAKING temperature upkeep time in cycles
 
-//Temperature Settings
+/*
+ * Temperature Settings
+ * 
+ * The ADC value can be calculated using the following line equation
+ * t=-0.7x+250
+ * 
+ * where X is ADC reading and t is target temp in degree C
+ * 
+ * Note that different setup (e.g. ref resistor value / NTC resistor value) might have different equations
+ * You can experiment with yours and get a few data point to plot your own line
+ */
 #define COOLDOWN_TEMP_ADC 255 //Room temperature
 //Preheat temp & power
-#define PREHEAT_TEMP_ADC 155 //160 degree C
-#define PREHEAT_PWR_PWM 130 //50% power output
+#define PREHEAT_START_ADC 143 //150 degree C
+#define PREHEAT_TEMP_ADC 122 //160 degree C
+#define PREHEAT_PWR_PWM 155 //60% power output
 //Reflow temp & power
-#define REFLOW_TEMP_ADC 123 //220 degree C
+#define REFLOW_TEMP_ADC 58 //220 degree C
 #define REFLOW_PWR_PWM 255 //100% power output
-//Overheat cutoff temp 
-#define CUTOFF_TEMP_ADC 100 //240 degree C
+//Overheat cutoff temp
+#define CUTOFF_TEMP_ADC 53 //230 degree C
 
 //Func def
 bool updateHeaterPowerState();
@@ -46,10 +57,10 @@ bool reflowComplete = false; //Indicate if the stopping is done because of reflo
   0: Standby
   1: Preheating
   2: Preheat Holding / Soaking
-  3: Reflowing 
-  4: Cooling down 
+  3: Reflowing
+  4: Cooling down
 */
-int reflowStages = 0; 
+int reflowStages = 0;
 int startCountdown = HOLDSTART_TIME; //Hold for HOLDSTART_TIME to start to prevent accidental touches
 int cycleCounter = 0; //Record cycle time up to 10 seconds
 int soakingCountdown = SOAKING_TIME;
@@ -58,14 +69,14 @@ int soakingCountdown = SOAKING_TIME;
 bool blinkState = false; //If blinking this will be switching between true and false
 bool blinkYellow = true; //Slow blink yellow if enabled (Standby). Do not enable both yellow and red at the same time
 bool blinkRed = false; //Slow blink red if enable (End of Reflow). Do not enable both yellow and red at the same time
-bool fastBlinkState = false; 
+bool fastBlinkState = false;
 bool fastblinkRed = false;
 
 
 //Real-time temperature control targets
 int targetTempADC = 255; //Target ADC reading to reach, 255 = room temperature
 int targetPwrPWM = 0; //Target PWM cycle for heater, 255 = full power, 0 = off
-int offset = 1; //Allow +-offset for the ADC reading before reheating / cooling
+int offset = 0; //Allow +-offset for the ADC reading before reheating / cooling
 
 void setup() {
   //Enable the touch buttons
@@ -93,49 +104,56 @@ void loop() {
 
   //Main reflowing logics
   //Add delay to the end of each conditions so each loop cycle is approximate 100ms
-  if (reflowing){
-    bool tempReached = updateHeaterPowerState();
-    if (tempReached){
+  if (reflowing) {
+    bool tempReached = updateHeaterPowerState(); //This action takes 100ms
+    if (tempReached) {
       //This stage temperature reached. Move to next stage
-      if (reflowStages == 1){
+      if (reflowStages == 1) {
         //Preheat stage completed. Enter soaking stage
         USBSerial_println("Preheat temperature reached. Soaking started");
+        targetTempADC = PREHEAT_TEMP_ADC; //Set temperature to soaking end temp
         reflowStages = 2; //Set reflow stage to soaking
         soakingCountdown = SOAKING_TIME;
         fastblinkRed = true;
-      }else if (reflowStages == 2){
-        //Wait for the soaking to complete and enter reflow stage
-        soakingCountdown--;
-        if (soakingCountdown <= 0){
-          //Soaking completed. Enter reflow stage
-          USBSerial_println("Soaking time ended. Reflow started");
-
-          //Set Reflow LED to high
-          fastblinkRed = false;
-          digitalWrite(LED_REFLOW, HIGH);
-
-          //Set to reflow temperature
-          targetTempADC = REFLOW_TEMP_ADC; //Set the target temp to reflow
-          targetPwrPWM = REFLOW_PWR_PWM; //Set power rating to reflow
-          
-          //Update the reflow stage to 3
-          reflowStages = 3;
+      }else if (reflowStages == 3) {
+          //Reflowing target temperature reached. Start cooldown and shut down heater
+          USBSerial_println("Reflow completed. Cooling down");
+          reflowStages = 4;
+          blinkYellow = false;
+          blinkRed = true;
+          targetTempADC = COOLDOWN_TEMP_ADC;
+          targetPwrPWM = 0;
+
+          //Reflow ended. Wait until stop being press to exit this state
         }
-      }else if (reflowStages == 3){
-        //Reflowing target temperature reached. Start cooldown and shut down heater
-        reflowStages = 4;
-        blinkYellow = false;
-        blinkRed = true;
-        targetTempADC = COOLDOWN_TEMP_ADC;
-        targetPwrPWM = 0;
-
-        //Reflow ended. Wait until stop being press to exit this state
+    }
+
+    if (reflowStages == 2) {
+      //Wait for the soaking to complete and enter reflow stage
+      soakingCountdown--;
+      if (soakingCountdown <= 0) {
+        //Soaking completed. Enter reflow stage
+        USBSerial_println("Soaking time ended. Reflow started");
+
+        //Set Reflow LED to high
+        fastblinkRed = false;
+        digitalWrite(LED_REFLOW, HIGH);
+
+        //Set to reflow temperature
+        targetTempADC = REFLOW_TEMP_ADC; //Set the target temp to reflow
+        targetPwrPWM = REFLOW_PWR_PWM; //Set power rating to reflow
+
+        //Update the reflow stage to 3
+        reflowStages = 3;
+      } else if (soakingCountdown % 100 == 0) {
+        USBSerial_print("Soaking cycles left: ");
+        USBSerial_println(soakingCountdown);
       }
     }
 
 
-  delay(1);
-  }else{
+    delay(1);
+  } else {
     //Standby mode
     digitalWrite(HEATER_PIN, LOW);
     blinkYellow = true;
@@ -143,32 +161,30 @@ void loop() {
   }
 
   //FastBlink handler, execute every 500ms
-  if (cycleCounter%5 == 0){
-    if (fastblinkRed){
+  if (cycleCounter % 5 == 0 && fastblinkRed) {
+    digitalWrite(LED_PREHEAT, LOW);
+    if (fastBlinkState) {
       digitalWrite(LED_REFLOW, HIGH);
-    }else{
+    } else {
       digitalWrite(LED_REFLOW, LOW);
     }
     fastBlinkState = !fastBlinkState;
   }
 
   //Blink handler, execute every 2 seconds
-  if (cycleCounter%20 == 0){
-    if (blinkYellow){
-      if (blinkState){
+  if (cycleCounter % 20 == 0) {
+    if (blinkYellow) {
+      if (blinkState) {
         digitalWrite(LED_PREHEAT, HIGH);
-      }else{
+      } else {
         digitalWrite(LED_PREHEAT, LOW);
       }
-    }else if (blinkRed){
-      if (blinkState){
+    } else if (blinkRed) {
+      if (blinkState) {
         digitalWrite(LED_REFLOW, HIGH);
-      }else{
+      } else {
         digitalWrite(LED_REFLOW, LOW);
       }
-    }else{
-      digitalWrite(LED_REFLOW, LOW);
-      digitalWrite(LED_PREHEAT, LOW);
     }
     blinkState = !blinkState;
   }
@@ -176,7 +192,7 @@ void loop() {
   //Cycle printout
   //USBSerial_println("cycle");
   cycleCounter++;
-  if (cycleCounter > 600){
+  if (cycleCounter > 600) {
     cycleCounter = 0;
   }
 }

firmware/reflow/utils.ino

@@ -36,19 +36,21 @@ bool updateHeaterPowerState(){
   if (currentADC <= CUTOFF_TEMP_ADC){
     digitalWrite(HEATER_PIN, LOW);
     USBSerial_println("!!! OVERHEAT !!!");
+    digitalWrite(LED_PREHEAT, HIGH);
+    digitalWrite(LED_REFLOW, HIGH);
     return false;
   }
   if (currentADC > targetTempADC + offset){
     //Temperature too low. Turn on the heater
     analogWrite(HEATER_PIN, targetPwrPWM);
-    USBSerial_print("+ ");
-    USBSerial_println(currentADC);
+    //USBSerial_print("+ ");
+    //USBSerial_println(currentADC);
     return false;
   }else if (currentADC < targetTempADC - offset){
     //Temperature too high. Turn off the heater
     analogWrite(HEATER_PIN, 0);
-    USBSerial_print("- ");
-    USBSerial_println(currentADC);
+    //USBSerial_print("- ");
+    //USBSerial_println(currentADC);
     return false;
   }else{
     //Within range. Keep the current state
@@ -70,10 +72,16 @@ void updateKeyStates(){
       reflowing = true;
       startCountdown = 0; //Prevent it from going underflow
       playStartingLEDBlinks(); //Play fast blink start warning
-      targetTempADC = PREHEAT_TEMP_ADC; //Set the target temp to preheat
+      targetTempADC = PREHEAT_START_ADC; //Set the target temp to preheat starting temp
       targetPwrPWM = PREHEAT_PWR_PWM; //Set power rating to preheat
-      digitalWrite(LED_PREHEAT, HIGH); //Light up the preheat LED
       reflowStages = 1; //Set the reflow stage to preheating
+
+      //Set the blinking LED status to off
+      blinkYellow = false;
+      blinkRed = false;
+      fastblinkRed = false;
+      digitalWrite(LED_PREHEAT, HIGH); //Light up the preheat LED
+      
     }
   } else {
     //Touch released
@@ -86,9 +94,11 @@ void updateKeyStates(){
     USBSerial_println("Reflow Stopped");
     //Set target temperature to room temp and shut down heater
     targetTempADC = COOLDOWN_TEMP_ADC;
-     targetPwrPWM = 0;
+    targetPwrPWM = 0;
 
-    //Set yellow LED to slow blink
+    //Set yellow LED to slow blinkRed
+    digitalWrite(LED_REFLOW, LOW);
+    digitalWrite(LED_PREHEAT, LOW);
     blinkYellow = true;
     blinkRed = false;
     fastblinkRed = false;