I'm using the standard button code to test a switch on a nano. When I use the built in LED, it works. when I use an external LED, the LED is on all the time and gets brighter when I push the switch. I suspect it might be a soldering issue, but can't see where...
// constants won't change. They're used here to
// set pin numbers:
const int buttonPin = 4; // the number of the pushbutton pin
const int ledPin = 10; // the number of the LED pin
// variables will change:
int buttonState = 0; // variable for reading the pushbutton status
void setup() {
// initialize the LED pin as an output:
pinMode(ledPin, OUTPUT);
// initialize the pushbutton pin as an input:
pinMode(buttonPin, INPUT);
}
void loop() {
// read the state of the pushbutton value:
buttonState = digitalRead(buttonPin);
// check if the pushbutton is pressed.
// if it is, the buttonState is HIGH:
if (buttonState == HIGH) {
// turn LED on:
digitalWrite(ledPin, HIGH);
} else {
// turn LED off:
digitalWrite(ledPin, LOW);
}
}
