I am very new to ARM controllers. All of my experience is with Atmel family, which I've been using for years.
I just got the nRF52 Development board and have loaded several of the example programs. All works fine.
I wanted to set one pin (pin 5) as output just to see how it works. I used the blinky example modified as
follows:
{
/* Configure board. */
bsp_board_init(BSP_INIT_LEDS);
nrf_gpio_cfg_output(0x5);
while (true)
{
for (int i = 0; i < LEDS_NUMBER; i++)
{
bsp_board_led_invert(i);
nrf_gpio_pin_set(0x5);
nrf_delay_ms(500);
nrf_gpio_pin_clear(0x5);
}
}