2017 Jun 09, 12:23 AM
(2017 Mar 27, 05:21 PM)dan,I setup the relay-interface you provided in your link below. I coupled that to a RPi3B and a bank of relays that turn on when their input is low. Everything appears to work from the perspective of driving the relays from SIP, but with one major issue. When the Pi boots and SIP starts up the relays being driven from the 74HC595 are ALL turned on (input low). This is a problem as the current draw is substantial. When I used the SIP run once interface the relay (which are on by default) are toggled off for the time set.My question is, how can I invert the action that turns the relay on (input pulled low by the 74HC595). I would like the relays to startup off and remain off (input high) until the SIP program instructs them to fire, at which time the input to the relay should be low.Thanks for your help,Rich Wrote: The 12 station limitation was because of the limited number of GPIO pins on the Raspi when the relay_board plugin was written.
If you are willing to build a simple shift register circuit you can add as many stations as you need:
https://github.com/Dan-in-CA/SIP/wiki/Relay-interface
Also, with this setup you will not need to use the relay_board plugin. it will work directly with SIP's native code.
Dan