Two nodes, one protocol
Until now I had a single prototype on the bench. Now there are two:
SHT-1 (shutter controller) and IO-6-6 (6 inputs, 6 relay
outputs). Both use the same common/ library.
The gateway polls each node in a loop and keeps state in memory. Frames carry integrity checks — and, as I found out the hard way, it really does earn its keep.
What went wrong
The first frames got lost every few seconds. Turned out it was a too-tight response timeout on the gateway side. Bumping the window dropped retransmissions to zero.
Up next
- Bootloader over the bus (so I can flash nodes without unscrewing them).
- Protocol docs in the repo — I’ll link them once they’re ready.