external device RST pin

[Stanislav Silnitskiy]

Hello! I'm in doubts about proper configuration of GPIO pin, which I'd like to be able to reset external device (DWM1000), connected to nRF51 by SPI. The datasheet says, the RST pin of device has to be connected directly to output pin of uController. After powering up, RST pin is driven to high impedance internally by device and to signal reset I have to pull it down for short time, then disconnect it.

Do I understand it right, that below config and operations have to be considered to implement this feature?

        nrf_gpio_cfg(
            pin_number,
            NRF_GPIO_PIN_DIR_OUTPUT,
            NRF_GPIO_PIN_INPUT_DISCONNECT,
            NRF_GPIO_PIN_NOPULL,
            NRF_GPIO_PIN_H0D1,
            NRF_GPIO_PIN_NOSENSE);

then to reset:

nrf_gpio_pin_set(pin_number);
// wait couple usecs
nrf_gpio_pin_clear(pin_number);

[run_ar]

Looks about right. As an example you can look at nrf_gpio_cfg_output in nrf_gpio.h in our sdk e.g:
__STATIC_INLINE void nrf_gpio_cfg_output(uint32_t pin_number) { nrf_gpio_cfg( pin_number, NRF_GPIO_PIN_DIR_OUTPUT, NRF_GPIO_PIN_INPUT_DISCONNECT, NRF_GPIO_PIN_NOPULL, NRF_GPIO_PIN_S0S1, //Not sure if it's necessary to use highdrive in your case, but disconnect is ok NRF_GPIO_PIN_NOSENSE); }

[Stanislav Silnitskiy]

ok! Thank you.