The antenna does NOT echo our sequence number — its replies carry their own
counter — so the previous seq-matching drained every reply and stalled status
updates. Revert to reading one reply per command, but flush any bytes left in
the stream before each command (drainStale): a reply left by a timed-out command
is discarded so the next read stays 1:1. readPacket also resyncs to the next STX.
This fixes the intermittent disconnects, phantom frequency jumps and wrong
element-length readings without depending on the seq.
Also: report motion for a short window right after a commanded move, so the
"moving" indicator and the Flex TX-inhibit fire the instant a band/pattern is
clicked instead of a poll (~2 s) later; the real motor state takes over once
polled.
sendCommand discarded the reply's sequence number and accepted whatever frame
came back. On a slow remote link a command that timed out left its late reply in
the stream, and the NEXT command read it as its own — crossing STATUS with
READ_BANDS/PROGRESS. That surfaced as phantom frequency jumps (a spurious
follow-loop re-tune), intermittent "reply too short" disconnects, and wrong
element-length readings (READ_BANDS getting the status frame).
Now every reply is matched to its request seq and stale/malformed frames are
drained (bounded), with readPacket resyncing to the next STX. Tested with a
net.Pipe that injects a stale reply ahead of the real one.
rouggy