RE: GPIO Config Issue

Simonr — Wed, 16 Sep 2020 06:18:55 GMT

You can use the NRF_GPIO_PIN_MAP to set port and pin number.

Best regards,

Simon

RE: GPIO Config Issue

Muqarrab — Tue, 15 Sep 2020 09:29:02 GMT

Thanks I have used P0.31 and its working now.
How can I use port 1 pins means how can I define them? (For example, how can I define P1.08?)

#define LED1_PIN ??

RE: GPIO Config Issue

Simonr — Tue, 15 Sep 2020 08:15:07 GMT

If you take a look at the back side of your nRF52840 DK, you can see that P0.05 is used for UART communication (RTS pin) by default. What is this pin supposed to do anyway? Is it just a LED or an output to the PuTTY terminal?

You can try using one of the free GPIOs mentioned in the DK user guide (any pins on header P2 and P3).

Best regards,

Simon

RE: GPIO Config Issue

Muqarrab — Mon, 14 Sep 2020 13:06:31 GMT

Hi,

I have changed the pin and try to use pin P0.05 but still not working.

#define LED1_PIN 5

Any suggestions, please?

RE: GPIO Config Issue

Simonr — Mon, 14 Sep 2020 06:07:36 GMT

P0.00 and P0.01 are, by default, used for the external LF CLOCK (32.768 kHz crystal) on the nRF52 series. When using a DK, you can't use these pins as GPIOs unless you disconnect the external crystal. On the DK, this can be done by cutting solder bridges SB1 and SB2, and soldering SB3 and SB4. This should disconnect the external crystal, and connect them to the GPIO outputs on your DK.

You will also have to configure your application to use the internal RC oscillator instead of the external LF clock if you want to use these GPIOs. This can be done by editing the following defines in your sdk_config.h file:

// <h> Clock - SoftDevice clock configuration

//==========================================================
// <o> NRF_SDH_CLOCK_LF_SRC  - SoftDevice clock source.
 
// <0=> NRF_CLOCK_LF_SRC_RC 
// <1=> NRF_CLOCK_LF_SRC_XTAL 
// <2=> NRF_CLOCK_LF_SRC_SYNTH 

#ifndef NRF_SDH_CLOCK_LF_SRC
#define NRF_SDH_CLOCK_LF_SRC 0
#endif

// <o> NRF_SDH_CLOCK_LF_RC_CTIV - SoftDevice calibration timer interval. 
#ifndef NRF_SDH_CLOCK_LF_RC_CTIV
#define NRF_SDH_CLOCK_LF_RC_CTIV 16
#endif

// <o> NRF_SDH_CLOCK_LF_RC_TEMP_CTIV - SoftDevice calibration timer interval under constant temperature. 
// <i> How often (in number of calibration intervals) the RC oscillator shall be calibrated
// <i>  if the temperature has not changed.

#ifndef NRF_SDH_CLOCK_LF_RC_TEMP_CTIV
#define NRF_SDH_CLOCK_LF_RC_TEMP_CTIV 2
#endif

// <o> NRF_SDH_CLOCK_LF_ACCURACY  - External clock accuracy used in the LL to compute timing.
 
// <0=> NRF_CLOCK_LF_ACCURACY_250_PPM 
// <1=> NRF_CLOCK_LF_ACCURACY_500_PPM 
// <2=> NRF_CLOCK_LF_ACCURACY_150_PPM 
// <3=> NRF_CLOCK_LF_ACCURACY_100_PPM 
// <4=> NRF_CLOCK_LF_ACCURACY_75_PPM 
// <5=> NRF_CLOCK_LF_ACCURACY_50_PPM 
// <6=> NRF_CLOCK_LF_ACCURACY_30_PPM 
// <7=> NRF_CLOCK_LF_ACCURACY_20_PPM 
// <8=> NRF_CLOCK_LF_ACCURACY_10_PPM 
// <9=> NRF_CLOCK_LF_ACCURACY_5_PPM 
// <10=> NRF_CLOCK_LF_ACCURACY_2_PPM 
// <11=> NRF_CLOCK_LF_ACCURACY_1_PPM 

#ifndef NRF_SDH_CLOCK_LF_ACCURACY
#define NRF_SDH_CLOCK_LF_ACCURACY 1
#endif

We strongly recommend using any other GPIOs if you have the opportunity, as it will save you a lot of work, and using the 32kHz crystal will give you much lower average current consumption than using the RC oscillator.

Best regards,

Simon