The station-control code rebuilt a fresh driver on every status poll and every
relay set. Stateful boards (Denkovi FTDI D2XX, USB-serial) hold an OS handle only
one opener can own, so the first poll opened the board and leaked the handle, and
every poll after failed with 'device in use' — the relays greyed out a second
after Save and auto-control never switched. Drivers are now cached per device and
reused, closed on config change. Adds a Test-connection button + detect feedback
in the device editor (reported by VK4MA).
- Denkovi (FT245 D2XX) now selectable as 4 or 8 relays (a 4-relay board just uses
the low nibble); NewDenkovi takes a count, driven by the device's Channels.
- New 'usbrelay' backend: cheap CH340/LCUS USB-serial boards over a COM port
using the common A0 protocol ([0xA0][relay][state][checksum]); write-only, so
Status is a shadow. Channel count configurable (1/2/4/8/16).
- StationDevice gains Channels; deviceRelayCount() drives label/relay counts for
the variable-size types. Device editor: channel selector + COM-port picker
(usbrelay) / FTDI-serial (denkovi).
Both untested on hardware; the A0 command set / Denkovi bit order may need a tweak
after a live test.
rouggy