Thanks in advance for any help.
Scenario Overview
In the real world, I am using one button to open two mechanical valves, but one of those valves should close after a period of time that we will hard code into the sketch, and the other valve stays open for as long as the button is pushed. For proof of concept, I am lighting two LEDs as stand-ins for the valves.
Pseudocode
If Button One is pressed, Valve One should Open, and Valve Two should also Open for 200ms then Close.
Initial Solution
Within the main loop, I look for the button to be pushed as part of an if statement. When that condition is passed, I used a while loop and timer to keep "valve2" open until the time is up. LEDs work, and all is superficially great. However...
The Issue
When my partner starts putting the actual mechanicals together, valve2 doesn't open because the while loop is cycling so quickly that the voltage required to initiate the opening of the valve is not high enough.
My Question
Is it possible to isolate (without using delays) the loop & evaluation of the timer condition from the main loop in order to allow full power to be sent to the valve mechanism (or LED in this case)? Or am I overthinking this whole thing (likely the case)?
The Code
const int button1 = 2; //Pin for switch 1
const int button2 = 3; //Pin for switch 2
const int valve1 = 12; //Pin for relay 1
const int valve2 = 13; //Pin for relay 2
// variables will change:
int state1 = 0; // variable for reading the pushbutton status
int state2 = 0; // variable for reading the pushbutton status
//THIS IS THE TIME IN MILLISECONDS FOR valve2 WHEN button1 IS DEPRESSED
int valve2time = 200;
void setup() {
//switches
pinMode(button1,INPUT); //Set button1 as input
pinMode(button2, INPUT); //Set button2 as input
//relays
pinMode(valve1, OUTPUT); //Set valve1 as output
pinMode(valve2, OUTPUT); //Set valve2 as output
Serial.begin(9600);
}
void loop(){
state1 = digitalRead(button1); //state1 returns the state of button1, up or down.
state2 = digitalRead(button2); //state2 returns the state of button2, up or down.
int duration = switchTime(); //Create variable to capture duration of switch press
if (state1 == LOW && state2 == LOW){ //if no buttons are pressed
digitalWrite(valve1,LOW); //make sure valve1 is off
digitalWrite(valve2,LOW); //make sure valve2 is off
}
else if (state1 == HIGH && state2 == LOW) { //if JUST button one is pressed
digitalWrite(valve1,HIGH); //turn on valve1
while (duration <= valve2time){ //as long as the timer is below or = to what we defined up top....
digitalWrite(valve2,HIGH); //...Turn on valve2...
break; //...Then stop the while loop...
}
digitalWrite(valve2,LOW); //...and finally turn off valve2
}
else if (state2 == HIGH){ //final condition, if button two is pressed
digitalWrite(valve1,HIGH); //turn on valve1
digitalWrite(valve2,HIGH); //turn on valve2
}
}
//return the time in ms that the switch has been pressed (LOW)
long switchTime(){
//these variables are static
static unsigned long startTime = 0; //the time the switch state was first detected
static boolean state; //the current state of the switch
if(digitalRead(button1) != state){ //check to see if the switch has changed state
state = ! state; //yes, invert the state
startTime = millis(); //store the time
}
if(state == HIGH){
return millis() - startTime; //switch pushed, return time in ms
}
else{
return 0; //return 0 if the switch is not pushed (in the HIGH state)
}
}