GPIO Pins for output (PB V3)

3

@Nick_W,
Those pins should work. Try something like this pattern, which will toggle them on off alternating between 25 and 26:

pinMode(25, OUTPUT)
pinMode(26, OUTPUT)

export function beforeRender(delta) {
  t1 = time(.05)
  digitalWrite(25, t1 > .5)
  digitalWrite(26, t1 < .5)
}
 
export function render(index) {
}

Pin 26 is on the top, then pin 25. There are small labels (IO26, IO25), but the fine printing is sometimes a bit too smudged to read easily.

I think you know this already, but for the benefit of others finding this page:

Keep in mind that for driving a relay a fairly large current is required, much more than a GPIO can output or sink. The inductance in the coils also tend to kick back, so feedback protection is needed. Usually this is done with a transistor or MOSFET and a diode. You can also get relay modules that have these drivers included and are intended to work with digital signals from a microcontroller.

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