An Arduino sketch for controlling a relay board with AC connections. This means that we use two relays per socket to cut off both the live and neutral connections at the same time. The sketch includes a serial interface using NMEA commands.
Edit KomaRelay.ino and define the number of relays and the digital pins they are connected into. By default the relay #4 (R4) is connected to the LED pin (13) for testing. If you plan to use multiple boards you should also update the board name to be unique.
Queries the board name and version number. This message is also sent automatically when the serial port is opened.
Example: $TEST*16
Response: $KOMARELAY,VER=1.0*34
Queries the current status of the relays.
Example: $STATUS*14
Response: $STATUS,R1=OFF,R2=OFF,R3=OFF,R4=ON*5E
Toggles one or more relays.
Example: $SET,R1=ON,R4=ON*47
Response: $SET,OK*6A
Errors: $SET,ERR*2B (parse error)