Random SPI data shifting at ~72kB/s throughput

[Musa]

Hello,

I am using nRF52 with ADS1292, and i am trying to sample at 8kHz with data throughput of 72kB/s, but some data is being randomly shifted giving me random spikes. This occurs on all available clock speeds to some degree. I am using Easy DMA. I am not getting any warnings or errors from the SPI driver as far as I can tell.

This issue does not occur at a lower data rate. Does this have something to do with overhead from the nRF SPIM drivers? I am also using I2C and other resources, but this also occurs with those additional resources disabled.

I'm trying to figure out what the limitation here is; is there a known limit on how many times you can call 'nrf_drv_spi_transfer' every second?

Thanks,

[MartinBL]

Hi,

1. Shifted how much and which way?
2. What SDK are you using?
3. Since you use Easy DMA I assume that you have not configured the SPI driver in non-blocking mode? That should make it less dangerous to call it too often, but you should wait and check the status of the transfer in the event callback anyway.
4. Have you checked the return codes from the SPI driver function calls for errors like this?