Change PPI Controlled SPI Message?

[Fan Jiaming]

Hi,

I am currently implementing an application which uses PPI to control SPI transaction when a HIGH-LOW transition is detected on a GPIO pin.

I first set up the transaction using nrf_drv_spi_xfer with RAM TX and RX buffer, also with the NRF_DRV_SPI_FLAG_HOLD_XFER flag. The program runs without problem.

I wonder if it is possible to change the content of what I send in between the PPI triggered transaction. For example I would like to send a 0x41 instead of 0x4B in the next transaction.

I have tried changing the RAM buffer content in the SPI event handler after each transaction, but it doesn't seems to work. I tried to set up nrf_drv_spi_xfer again that points to differnt buffer and reconnect it to PPI, but it also doesn't do the trick.

Is there a way?

[Petter Myhre]

Sounds like you want to use repeated transfers with the NRF_DRV_SPI_FLAG_TX_POSTINC flag. Have you looked into that?