Using a Raspberry Pi + Octopi to manage your printer

[gmay3]

This way I can control the power, lights, and fans when I'm at the printer, or I can control them when I'm away over OctoPi. I could flip a relay through the webpage to turn the lights on, then flip the switch on the printer to turn them off again, and vice-versa.

This sounds awesome! Let us know how your development/build goes!

When I had it connected to the TV I went into the wifi manager and saw that it had not yet connected to my wifi so I clicked connect. I don't know why this was the case because I have been able to get it to work by just power cycling the board when it is not connected to the TV.

Is there a way to access a debug terminal to see the octoprint server process running?

[AbuMaia]

Not that I know of. I haven't been able to find any way to run the server with debug info through the terminal yet.

I finally received the wires to connect my RasPi to the relay board. I followed the instructions here: https://github.com/foosel/OctoPrint/...-from-your-RPi I used the relay board listed on that page from Amazon. I have power going through relay 4, lights through 3, and fans through 2. Relay 1 is still unused. The relays are SPDT, so when combined with three more SPDT switches, I get the double-switch action.

The power goes into common on the switch, NO connects to the relay NC, and the switch NC is connected to the relay NO. The relay common takes the power into the power supply. (Yes, I checked to make sure the relay and switch could handle 120v AC.)

The fan and light switches are run the same way. Power out from the power supply into common on the switch, NO-to-NC and NC-to-NO connections to the relay, and relay common out to the fans and lights. I should note I'm running the - wires through the switches and relays. The + side just connects directly.

i had to install wiringPi in order to get the commands to control the GPIO pins from the webpage. I would recommend NOT using physical pin 8 (wPi pin 15, BCM pin 14) to control a relay, as when the RasPi starts up, that's the TxD pin, and it will rattle the relay and send intermittent power to whatever you're switching. I used physical pin 12 instead.

edit: I've also written a small script to call from the OctoPi webpage that let me condense six commands (Printer On, Printer Off, Fans On, Fans Off, etc) into three (Toggle Printer, Toggle Fans, Toggle Lights).

pintoggle goes into ~/scripts:

#!/bin/bash
#read the pin and toggle mode
pin=$1
state=$(gpio read $pin)
if [ $state = "1" ]; then
gpio mode $pin out
else
gpio mode $pin in
fi

This goes into the config.yaml for OctoPrint:

  - action: toggle printer
    command: bash ~/scripts/pintoggle 1
    confirm: You are about to turn the printer On or Off
    name: Toggle Printer
  - action: toggle lights
    command: bash ~/scripts/pintoggle 7
    confirm: false
    name: Toggle Lights
  - action: toggle fans
    command: bash ~/scripts/pintoggle 9
    confirm: false
    name: Toggle Fans

Use whatever pin numbers you end up using.

[kd7eir]

Never mind - it was "helpful" caching that was not showing me the changes when I was expecting them.

I entered everything exactly as you have it shown here, but I could never get the actions to show up in the menu. I can run the script that you wrote from terminal and it works properly, so I must be doing something wrong in how I am entering the actions. Strangely, any other actions that I create, besides the ones you have here, will show up in the menu.

[gmay3]

Hey Kd7eir, welcome to the forums! Glad you were able to get past the "helpful" caching haha. Do you have octoprint up and running then?

[dacb]

Outstanding stuff, Abu!

[kd7eir]

Hey Kd7eir, welcome to the forums! Glad you were able to get past the "helpful" caching haha. Do you have octoprint up and running then?

Thank you gmay3

I do have octoprint up and running, complete with camera. It's very nice to have complete control of the printer remotely as well as being able see exactly what it's doing.

[gmay3]

Very cool! Yeah I have liked it so far. Sometimes it's a little buggy but nothing a "reset octoprint" or browser refresh can't usually fix.

[kd7eir]

Very cool! Yeah I have liked it so far. Sometimes it's a little buggy but nothing a "reset octoprint" or browser refresh can't usually fix.

I have definitely become familiar with those. I've only had one print that just would not work through octoprint. It was a case for a Sainsmart 4 relay board. It would constantly throw an error about line numbers being wrong. Copied the gcode straight to the SD card and it printed fine from there. That makes my reliability rating about 99% for octoprint - not too bad for free software.

[gmay3]

Absolutely, for about 50 dollars for all the stuff needed, you can't beat it!

[Stigern]

Just got my RPI up and running with OctoPi

Btw, are there plugins or such available? Would be very cool to have a plugin which shows where the printer extruder is at all times :P