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,

[Musa]

Hello, I don't think wiring or ground is an issue. I am working with a PCB design that we have used for some time, with good results at lower sampling rate (lower throughput). It looks like not all transfers are completed correctly. Many times data are replaced with zeros, and other times it is just garbage data. I cannot pin down exactly what the issue is.

Is there anything I should try to get more information?

Thanks,