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+--- Thread: more than 12 channels (/showthread.php?tid=70)
RE: more than 12 channels - dan - 2017 May 16
If you add more stations you can use the pins that match the other numbers in the list and you should not need to change anything.
Dan
RE: more than 12 channels - joeb@drumwerx.com - 2017 May 17
Great!! I have 1 controller with 12 Zones and it could go to 13, this is perfect. I have another at 12 that can go to 13.
THANKS!!
RE: more than 12 channels - 22ndst - 2017 Jun 09
(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
RE: more than 12 channels - dan - 2017 Jun 09
I am working on a solution.
At the present there is an update to SIP on GitHub that has an option called "Active-Low relays" under Station handling on the Options page. It provides a partial solution.
Once the system is powered up the relays behave as expected. The update inverts the logic of the shift registers. There is still a problem when the system is starting up. That is being worked on.
Dan
RE: more than 12 channels - 22ndst - 2017 Jun 10
(2017 Jun 09, 03:49 AM)dan Wrote: I am working on a solution.
At the present there is an update to SIP on GitHub that has an option called "Active-Low relays" under Station handling on the Options page. It provides a partial solution.
Once the system is powered up the relays behave as expected. The update inverts the logic of the shift registers. There is still a problem when the system is starting up. That is being worked on.
Dan
Dan,
Thank you for changing things up so quickly. I updated the SIP version and then edited the gpio_pins.py file to uncomment out the lines you earmarked. The relays are behaving now, but as you know only shut off once SIP is started, so I will look forward to additional changes to come forth that will control the start up condition.
I had a similar issue with Cayenne MyDevices. Someone discovered a config file that was read and acted on fairly early in the start up and that patched things up for now. Seems the Raspberry Pi has no way of storing the state in non-volatile memory like the Ardunio does.
RE: more than 12 channels - dan - 2017 Jun 10
I think I found a solution to the power up problem.
All you need to do is add a 10k pull up resistor from pin_sr_noe (pin 11 on the Pi) to the 5v line.
Actually on the shift register diagram it would be between the purple input wire from the Pi to the 5V rail.
I tried it here and it is working using a SainSmart relay board.
I still need to do some further testing. It may be possible to enable a pull up on the Pi through software. I'll post back after I test. Short on time riight now
Dan
RE: more than 12 channels - davidjustin - 2017 Jun 10
(2017 Jun 10, 01:11 AM)dan Wrote: I think I found a solution to the power up problem.
All you need to do is add a 10k pull up resistor from pin_sr_noe (pin 11 on the Pi) to the 5v line.
Actually on the shift register diagram it would be between the purple input wire from the Pi to the 5V rail.
I tried it here and it is working using a SainSmart relay board.
I still need to do some further testing. It may be possible to enable a pull up on the Pi through software. I'll post back after I test. Short on time riight now
Dan
Thank you for working on this!
I was struggling to get my Active Low boards working. After adding the 10k pull-up resistor it works as you described!
I was looking at this earlier today and noticed the DIY relay diagram was updated to include the wiring for the transistor, but now it seems to have reverted back to the earlier version. It is working for me with the transistor wired up, but is it necessary?
Also, I don't see an "Active-Low relays" option in the station handling, did that get left out?
David
RE: more than 12 channels - dan - 2017 Jun 10
The transistor is not needed, just the pull-up resistor.
The option for active-low relays should be in the latest update of SIP. I will check to be sure and will be pushing a new update later today with some cleaned up code.
Dan
RE: more than 12 channels - 22ndst - 2017 Jun 10
Dan,
The pull up resistor worked for me as well. From an upgrade perspective, it's great that you are inserting the active-low relay option on the option page. I will look for it later today.
Thank you again for the fine work.
Rich
RE: more than 12 channels - dan - 2017 Jun 10
The upgrade is now on GiitHub. Version 3.2.22 and has the Active-low relay option under Station Handling on the Options page.
I'm very glad to have Active-low relay boards working with the shift registers now. Those seem to be the most common type.
Now I just need to update the instructions and circuit diagram on the wiki.
Thanks for bringing this up.
Dan