Does SPI frame length support 32-bit?

[valerian123]

My SPI slave sensor requires a 32-bit frame length. The CS (Chip Select) signal needs to be switched for each 32-bit frame interval, and it also supports DMA (Direct Memory Access) transmission. Does the nRF5340 or nRF52840 support this?

[Susheel Nuguru]

Hi Xiao, all of our products are working with with fixed 8-bit SPI frames.
For 32-bit sensors, use 4-byte transfers and toggle CS per frame through GPIOTE/PPI control. We dont have a template code to show this but a lot of other users have achieved this using GPIOTE/PPI combo to toggle CS if you set 4-byte transfers (MAXCNT = 4)

[valerian123]

Thank you. We are going to give it a try.