Send more than 255 bytes on SPI slave on nrf52832

[Akshay]

Is it possible to send more than 255 bytes on SPI when nrf52832 is used as slave. A few solutions use SPI Master with easyDMA and ArrayList to do this. Will the same solution work for SPI slave?

[bjorn-spockeli]

Hi Akshay,

the SPI Slave Peripheral in the nRF52832 only has the EasyDMA feature, it does not have the ArrayList(Autolog) feature like the SPI Master.

This means that you will only be able to send 255 bytes (since the TXD.MAXCNT is a 8-bit register) without involving the CPU. After 255 bytes you have to update the pointers to the TX and RX buffers and start another transaction.

Best regards

Bjørn

[Akshay]

Thanks for the help.

[josschne]

If I do not have control over the SPI master, and it insists on sending >255 byte packets, is there any workaround or solution to receive the large packet?