Arduino millis not work - c

Question

I have written a huge program for Arduino.
I have tested each function individually, and all go fine except the function where I need millis().
Now carry the code block that I encounter any difficulties.
the variable T contains the number in seconds for this is multiplied by 1000
void onResistance(){
Input = sensors.getTempC(tempSensor);
sensors.requestTemperatures(); // prime the pump for the next one - but don't wait
digitalWrite(RelayPin, HIGH);
//more code
Input = sensors.getTempC(tempSensor);
sensors.requestTemperatures(); // prime the pump for the next one - but don't wait
if(Input<Setpoint){ onResistance(); }
else{ digitalWrite(RelayPin, LOW); istru++; return ; }
return ;
}
void statTemp(){
unsigned long currentMillis = millis();
if(currentMillis - previousMillis > ttemp){
previousMillis = currentMillis;
Input = sensors.getTempC(tempSensor);
sensors.requestTemperatures();
lcd.setCursor(0,1);
lcd.print(F("T. Att.:"));
lcd.print(Input);
lcd.write(1);
lcd.print(F("C"));
if (Input<Setpoint) {
digitalWrite(RelayPin, HIGH);
statTemp();
} else if(Input>Setpoint || Input == Setpoint) {
digitalWrite(RelayPin, LOW);
statTemp(); }
} else if(currentMillis - previousMillis < ttemp) { playShortBeep(); istru++; return; }
return ;
}
void startFan(){
Input = sensors.getTempC(tempSensor);
sensors.requestTemperatures(); // prime the pump for the next one - but don't wait
digitalWrite(FAN_PIN, HIGH);
//more code
Input = sensors.getTempC(tempSensor);
sensors.requestTemperatures(); // prime the pump for the next one - but don't wait
if(Input>Tm){ startFan(); }
else{ digitalWrite(FAN_PIN, LOW); istru++; return ; }
return ;
}
void controll(){
if(!start)
return ;
if(start){
if(istru==0){
onResistance();
}
if(istru==1){
ttemp = (T * 1000) + millis() ;
statTemp();
}
if(istru==2){
startFan();
}
if(istru==3){
start =false;
opState = OFF;
playShortBeep();
playShortBeep();
playShortBeep();
istru=0;
}
}
delay(100);
return ;
}
I need for the time T the function statTemp remains running conducting checks if written in it.
sorry for my bad english

Answer 1

So you want to stay in the function statTemp() until time T has passed?
Then something like this might work
void statTemp(){
unsigned long currentMillis;
unsigned long enteringMillis = millis();
while (((currentMillis = millis()) -enteringMillis) < T)
{
if(currentMillis - previousMillis > ttemp){
etc etc etc....
}
return ;
}
Notice the MIGHT. I don't know if millis is updated at every timer interrupt or just in the loop function; in the latter case, you will be stuck forever in the function.
Consequently i suggest you not to do this, but think at another approach: an FSM which handles the function to be executed. It's a cleaner way to proceed and less error-prone.
Bye
EDIT:
Here is a complete working example. In this example, the function myfunc is executed for 10 seconds; during this time the board performs some actions (in this example serial output). When 10 seconds pass, the program goes on, thus repeating the loop function.
unsigned long previousTime;
void myfunc();
void setup() {
Serial.begin(9600);
}
void loop() {
Serial.println("I'm in the loop function");
myfunc();
}
void myfunc()
{
unsigned long currentTime;
unsigned long enteringTime = millis();
while(((currentTime = millis()) - enteringTime) < 10000)
{
if(currentTime - previousTime > 1000)
{
previousTime = currentTime;
Serial.println("I'm in the custom function");
}
}
}
HOWEVER my suggestion is still the same: instead of blocking the execution inside of a function, use a finite state machine; it's much more flexible and easier to understand, implement and edit.