When writing an SPI protocol decoder, almost every higher-level PD has to internally keep track of the CS status, buffer up the individual bytes as they are received, and then interpret them when CS becomes deasserted. I feel that writing SPI-attached PDs would be simpler if the SPI decoder itself would perform this basic step for them.

Currently it has two types of data output:

  BITS [list of [bitvalue, ss, es] * 2] * 2
  DATA bytevalue * 2

I'd like to propose a new type, called perhaps "TRANSFER", whose contents are the full byte-wise collection of DATA bytes to cover the entire CS transaction.

Thus, where currently it outputs e.g.

  ['CS-CHANGE', 1, 0]
  ['DATA', 0x10, 0xff] at times ss=100, es=110
  ['DATA', 0x23, 0xff] at times ss=111, es=121
  ['CS-CHANGE', 0, 1]

I'd like to add a new single extra item that looks like:

  ['TRANSFER',
     [[0x10, 100, 110], [0x23, 111, 121]],
     [[0xff, 100, 110], [0xff, 111, 121]]]

That is, data1 relates to MISO and data2 relates to MOSI as with DATA, but the value in each is a list of elements, each element being a [bytevalue, ss, es] triple.

This structure would make it much simpler to write most SPI-based PDs.