Issues With SPI master

RE: Issues With SPI master

Rilleaa — Mon, 04 May 2020 12:27:31 GMT

It works fine now no problem with the event handler, the issue was how i handled the information within the event handler.

Thx for the help :).

RE: Issues With SPI master

Dmitry — Sat, 02 May 2020 19:03:49 GMT

Hmm, it shouldn't behave this way. SPI doesn't look at sending characters, sizeof(m_tx_buf)-1 should work the same way as sizeof(m_tx_buf). Maybe LA trace could clarify things..

RE: Issues With SPI master

Rilleaa — Fri, 01 May 2020 21:34:51 GMT

Hi Dmitry thx for the reply.

I will take a look att this tomorrow when i have access to the logic analyzer again.

What i did notice is when i changed the code to m_length = sizeof(m_tx_buf)-1; the event handler i have for the spi wasn't called. Could that be because nrf_drv_spi_transfer() is looking for that terminationg zero as a indication that transfer is complete?

RE: Issues With SPI master

Dmitry — Fri, 01 May 2020 19:45:42 GMT

Hi,

sizeof() operator returns memory size allocated for an object - in case of string, it includes terminating zero character. You can either simply substract one, or define your string as an array of chars (without trailing zero):

#define TEST_STRING {'T','H','I','N','G','Y'}