GPIO control

[roger.k]

Hi. I'm using PCA10040. I'm trying to control GPIO. But I can't control PIN 09, 10. Let me show you my source code.

int main(void)
{

    /* Configure LED-pins as outputs. */
	for(int i=5;i<26;i++)
	{
	    nrf_gpio_pin_set(i);
	    nrf_gpio_cfg_output(i);
	}

    /* Toggle LEDs. */
    while (true)
    {
		for(int i=5;i<26;i++)
		{
			nrf_gpio_pin_set(i);
		}
		nrf_delay_ms(500);
		for(int i=5;i<26;i++)
		{
			nrf_gpio_pin_clear(i);
		}
		nrf_delay_ms(500);
    }
}

What is the problem? How can i fix it?

I need your help.

[MartinBL]

Hi,

Those are the pins used for the NFC. You need to clear the first bit in the NFCPINS UICR register in order to use them as GPIO pins.

[roger.k]

Thank you for your reply. How can I clear the NFCPINS UICR register? Can you give me a source code? I hope your reply.

[MartinBL]

Did you try both of Bjørn's suggestions here?