nrf52832 spi (PSEL.SCK) timing

[yanli_1226]

I want to use nrf52832 SPIM， In nRF52832_PS_V1.4 it described that "An SPI master transaction is started by triggering the START task.Following a START task, the SPI master will generate an END event when both ENDRX and ENDTX have been generated." ，then how can I know if one byte has been transmitted (not after all TX_BUF bytes is transmitted，because I want to add gaps between bytes)?

I used the code below(picture left)，and the SPI timing is like the picture right.

      

My question is I want to add gaps between each 8 clock, just like bellow?

[MartinBL]

Hi,

The whole point of EasyDMA and the ability to specify a buffer of a arbitrary length is to be able to transfer the entire buffer without CPU intervention or delays. If you need delays between every single byte, you will have to send 1 byte long buffers one at the time and make your delay in software. 

[yanli_1226]

Thanks.

when I send 1 byte long buffer at a time without delay, the gaps between bytes are 2.2us, I only want the gaps time to be less than 10ns. there is my code bellow, how can I get the gaps between bytes less than 100ns?

 

[yanli_1226]

Now I use NRF_SPIM0->SHORTS in order to cut short the time between bytes, but it still has 1.4us，I need the time to be less than 100ns?