Spi_issues

[Nero]

Hello, I am using nRF SDK 12.2.0 , with nRF52832 on pca10040 hardware, and working with the example in examples/peripheral/spi/main.c to develop a driver for LIS2DE12.

Initially I was working on integrating a library, and found via Tera term (uart communication) that every other SPI byte output had a 0xFF appended . every other call to nrf_drv_spi_transfer(), The only modification I made was to change the SPI pins. Any ideas as to what's going on?(/attachment/aafcc184333cd473cba77b3053097890)

Thanks!

[Roger Clark]

Did you connect your logic analyser to confirm that the data being sent is indeed -0xFF?

[Nero]

thanks , I don t have a logic analyser . this is my project link text .I would be very grateful if you could help me

[ovrebekk]

Hi Amed

It sounds like you have hit issue 58 in the nRF52832 errata (scroll to page 12).

This bug will make the SPI output an extra byte when you are only sending/receiving a single byte. If you send more than 1 byte the issue does not occur.

There is a workaround described in the errata that makes it possible to stop the SPI in time, and avoid the second byte.

Best regards
Torbjørn

[Nero]

Hello Torborjn , Thanks , As I'm say i had the problem SPI bus ,but i don't have a logic analyzer , but when debug my project i 'm getting the following result. I will see if this is really this problem nRF52832 errata .thanks a lot for response.

[Nero]

Is it normal that I have RXD.MAXCNT = 0 TXD.MAXCNT <= 0