I have implemented a working GPIF state machine that captures N individual lines of data, with one DMA buffer the size of one line. At the end of acquisition, the state machine loops indefinitely at the final state waiting for a vendor command to reset the acquisition for a new frame.
I've been struggling with commiting/flushing data however. I'll either get the last line of one acquisition prepended to the start of the next, or the current acquisition never completes (Begin/Wait/FinishDataXfer will time out), depending on the size of the acquisition.
Things that are unclear to me:
1) Do I need to flush at the end state of the GPIF if I've made sure to capture exactly one buffer of data? It seems like if I don't flush I may or may not get data returned.
2) I'm really confused about the remark in the reference manual saying that I need to read data while doing a commit to avoid a zero length packet. I tried this (forcing the acquisition to end with a half full buffer), and without it the acquisition did not return data. With the read data it did, but I get one extra sample. Is that expected?
3) For CY_U3P_DMA_TYPE_MANUAL_MANY_TO_ONE, is the callback called during the FLUSH state? Or only when the buffer is actually full?
