Relay connection to gpio

[dan]

If you are using the relay_board plugin the pins are defined in SIP/plugins/relay_board.py line 55.

If you are using a shift register interface the pins are defined in SIP/gpio_pins.py starting on line 95.
You can get a large number of stations while using only a few GPIO pins with a shift register interface such as the one described in the SIP wiki:
https://github.com/Dan-in-CA/SIP/wiki/Relay-interface

This works best with high level trigger type relays.