One CS-framed transaction: marker + 32-bit count + MOSI + read-latency
skip + MISO, MSB-first on the wire, matching OpenOCD's jtagspi so the
quartiq proxy bitstreams work unchanged. Half-duplex (tx,txlen,rx,rxlen)
signature, single-device chain.
NOT yet validated on hardware — protocol follows the OpenOCD reference
but has not been confirmed against a live proxy + flash. Validation
(read JEDEC ID on the KCU105) is the next step.
François
0c9cc679f1