Issue with setting GPIO pins as output.

[gojiman23]

Hello, I am new to developing with nrf and have been trying to follow tutorials on individually setting pins as output. I am working on just getting a specified pin to blink an LED.

My code is as follows:

#define PIN27 27

int main(void)
{
    nrf_gpio_cfg_output(PIN27);
    nrf_gpio_pin_clear(PIN27);
    while(1)
    {
        nrf_gpio_pin_toggle(PIN27);
        nrf_delay_ms(1000);
    }
}

For some reason, the LED is not blinking even though it seems I've followed the code online perfectly. Can anyone see the issue?

[johnny]

This look like correct

what is your hardware design?

maybe your pin use pin27 not P0.27

[gojiman23]

I'm using the nrf52840PDK. what is the difference between pin27 and P0.27?

[haakonsh]

p0.27 is not the same as pin 27 on a given chip package.

Are you sure you're measuring the correct pin? See Connector interface for the position of p0.27

[gojiman23]

So how would I access p0.27 instead? Thank you for your help

[haakonsh]

P0.27's location on the DK is described in the link in my last post.  Your code is correct btw.

[gojiman23]

Thanks, so I figured out that I am indeed using the right pin. If i switch the code to toggle Pin 16 then it works just fine on the board's LED, but for some reason an external LCD connected to pin 27 will not. Are there additional adjustments I have to  make to my code for that or is it more likely to be a hardware issue?

[gojiman23]

Sorry, I meant an external LED*