interface ds3234 with nrf51 dk using spi

[rushin]

hello there i want to interface nrf51 dk with ds3234 using spi. i see spi master example. how to assign SPI I/O pins. can you tell me how to do it?? i find SPIMO_SCK_PIN. how to know about pin numbers??

[Stefan Birnir Sverrisson]

Hi

The pin configuration for nRF51 peripherals is usually fetched from a configuration file specific for the development board that you are using. If you are using the the nRF51-DK (PCA10028) then the configuration is in file \nRF51_SDK_10.0.0_dc26b5e\examples\bsp\pca10028.h. In this file, the configuration for e.g. the SPI master 0 and SPI master 1 is defined as

#define SPIM0_SCK_PIN       4     /**< SPI clock GPIO pin number. */
#define SPIM0_MOSI_PIN      1     /**< SPI Master Out Slave In GPIO pin number. */
#define SPIM0_MISO_PIN      3     /**< SPI Master In Slave Out GPIO pin number. */
#define SPIM0_SS_PIN        2     /**< SPI Slave Select GPIO pin number. */

#define SPIM1_SCK_PIN       15     /**< SPI clock GPIO pin number. */
#define SPIM1_MOSI_PIN      12     /**< SPI Master Out Slave In GPIO pin number. */
#define SPIM1_MISO_PIN      14     /**< SPI Master In Slave Out GPIO pin number. */
#define SPIM1_SS_PIN        13     /**< SPI Slave Select GPIO pin number. */

So change those defines in order to connect SPI master to different GPIO pins.

Then in order to enable SPI0 master in e.g. the spi_master example, you must do that in the driver configuration file \nRF51_SDK_10.0.0_dc26b5e\examples\peripheral\spi_master\config\spi_master_pca10028\nrf_drv_config.h by defining

#define SPI0_ENABLED 1