I have a packet of data on an SSI port that can vary in length up to 1024 bytes. The SSI port is configured as a slave. Currently, the uDMA module is used to copy this data into SRAM and this works well, but only if the packet is a fixed size. The Frame Select pin goes low for the entire transaction and after a small hold time, returns high after the transaction finishes.
My idea is to use the frame select pin to determine when the packet has completed, as I cannot rely on a simple uDMA transfer completion interrupt (as the interrupt will only fire when the uDMA size bytes have been transferred)
So I would need to set up an interrupt on the rising edge of the appropriate GPIO - the problem is the pin is already assigned to the nFSS function - can it still have an interrupt attached?
Thanks,
