High drive capability

[julienh]

Hi,

I'm developing a product with the NRF52832.

I have one Blue LED (APA2107LVBC) which is driven directly by a GPIO as shown below :

With a typical Vf of 2.65V, the current should be limited to 4.3mA.

My GPIO is configured in High Drive H0D1

    nrf_gpio_cfg(LED_1,                       
                NRF_GPIO_PIN_DIR_OUTPUT,
                NRF_GPIO_PIN_INPUT_DISCONNECT,
                NRF_GPIO_PIN_NOPULL,
                NRF_GPIO_PIN_H0D1,      
                NRF_GPIO_PIN_NOSENSE);
    nrf_gpio_pin_clear(LED_1);


The LED never lights up even if the current is bellow the limit (I'm not consuming current on other GPIO). 
The LED lights up if I connect it directly to GND with a wire.

Is there something that I have misunderstood with the way of using High drive output?

Thank you

[Håkon Alseth]

Hi,

 

Your configuration in firmware and schematic looks good. Polarity is OK, since it lights up when you connect it to GND.

Which GPIO are you using for this ("LED_1")?

Best regards,

Håkon

[julienh]

HI,

I'm using GPIO P0.21. 

Best regards

[AmbystomaLabs]

According to the blog you need to remove the definition for CONFIG_GPIO_AS_PINRESET since by default it is the reset pin.

See here:

devzone.nordicsemi.com/.../disabling-pin-21-of-nrf52832

[julienh]

That works. Thank you.