Arduino Loop Error: Waits several seconds to respond to input change - c++

Question

I am trying to write a simple control program for an Arduino Uno for an experiment I'm running at work. Quite simply it just needs to read if an input pin is high, if it is wait 10 milliseconds to turn an output pin high, hold for 10 milliseconds then go low, else the output pin is low.
My problem is that when I run this it ignores the initial delay altogether, and the output pin stays high for several seconds before going low. (using delayMicroseconds)
void setup()
{
pinMode(8, INPUT);
pinMode(13, OUTPUT);
}
void loop()
{
if (digitalRead(8) == HIGH)
{
delayMicroseconds(10000); //wait 10 milliseconds
digitalWrite(13, HIGH); // Pump on
delayMicroseconds(10000); // holds for pulse width of 10 millisecond
digitalWrite(13, LOW); // Pump off
}
else
{
}
}
I've tried setting up something simpler for debugging using the delay function to wait for a second, then turn output pin high, wait for a seconds, then turn output pin low. I did this so I could visually debug using the arduino's built in LED. the result is that it actually continues to run the loop 3 times after the input pin goes low. (using delay)
void setup()
{
pinMode(8, INPUT);
pinMode(13, OUTPUT);
}
void loop()
{
if (digitalRead(8) == HIGH)
{
delay(1000); //wait 1 second
digitalWrite(13, HIGH); // Pump on
delay(1000); // hold for 1 second
digitalWrite(13, LOW); // Pump off
}
else
{
}
}
I can't seem to figure out why it's doing this. I've looked all over and can't seem to find information about why this would happen. I might be missing something really simple, I am not an experienced coder, I just write what I need to run experiments. I've tried reading and writing to the pin register directly using c code, and switching from an if statement to a while loop, none of them fixed the problem. Any insight is greatly appreciated.

Answer 1

You should look at the internal pull-up resistors on the Arduino. You can debounce the signal from your button entirely with software:
void setup() {
pinMode(2, INPUT_PULLUP);
}
void loop() {
if (digitalRead(2) == LOW) // NOTE THAT PULLUPS REVERSE YOUR LOGIC
{
delay(1000); //wait 1 second
digitalWrite(13, HIGH);
delay(1000);
digitalWrite(13, LOW);
}
}