SPI CS not toggled during transfer

Question

Hello, 
 I want to connect one board trough SPI to my nRF51-DK. Using SDK11 and SD130, the nRF51-DK is the SPI master, I call the function nrf_drv_spi_transfer() but the CS Pin is never toggled. To solve this I changed it manually before and after the transfer, but this is not a good solution. I dug into the functions and discovered that this should be done automatically by this part of the code (from what I understood): 
 if (p_cb->ss_pin != NRF_DRV_SPI_PIN_NOT_USED)
 {
 nrf_gpio_pin_clear(p_cb->ss_pin);
 }
 
 and after the transfer 
 if (p_cb->ss_pin != NRF_DRV_SPI_PIN_NOT_USED)
 {
 nrf_gpio_pin_set(p_cb->ss_pin);
 }
 
 The NRF_DRV_SPI_PIN_NOT_USED is defined as 0xFF , do I need to change it? Is there any other way to do this? 
 Thank you for the help, 
 Jorge Costa

Jorge · Accepted Answer

I was using an example code from other company and they had cleared the cs pin on a interrupt. This was causing it to be cleared right after I tried to initiate a spi transfer.