View Full Version : Hacking garage door opener controller board

05-23-2006, 11:04 AM
I am building a positioning system and thought a great starting point would be to use a Genie garage door opener and use my Basic Stamp II to signal it to “open” and “close”. It has a soft start DC motor (1/2 HP) driving a jackscrew. Problem: inertial loads (even with the soft start) exceed the safety (obstacle detection) threshold that stops or reverses the motor. I’d love to throw out their controller and all its garage door safety stuff and use the HB25 with the BSII, but the 120VDC motor is out of range for the HB-25. Here’s the fixes I’m considering unless ya’ll have any better ideas.

Option 1) I’ve identified what I think is a 2200 ohm resistor on the controller board that I might short-out to increase the torque threshold where the controller reverses the motor.

Option 2) Identify which of the 10 wires between the controller board and the motor board in the Genie case is the speed modulating signal and intercept it here, replacing it with my own PWM signal from the BSII. Any chance of this actually working? – I don’t even know if the motor board is PWM controlled. But this approach would allow me to keep all the power circuits that come with the Genie system.

Option 3) Find a BSII compatible motor controller that does fit the 120V range.

Option 4) Throw away everything but the jackscrew, get a 12VDC hp motor and use the HB25. But now I also need a 400 watt, 33 amp, 12V power supply. And I have to build the mechanical interface to the jackscrew and new mounting.

05-25-2006, 06:38 AM
not familiar with the Genie garage door opener
does your manual show a push button set up you can use instead of
or with your remote possibly that hooked to the back of the motor unit?
if so check that voltage source
possibly a 24 volt relay contact

05-25-2006, 10:21 PM
Thanks Japer for the reply.

The system does have a hardwired control pad, but either input (remote or keypad) triggers the motor start/control through the same controller board. The manual does say you can defeat the safety-beam system by continuing to hold the hardwired activate button. But apparently you still can't defeat the torque limiter this way which is my problem. Since no one has yet suggested otherwise, I will risk the $80 controller board and solder in my resistor bypass to see if that works. Probably won't get to it till tomorrow though. Will post the results: success or failure.

05-26-2006, 11:44 AM
I decided to probe the pins between the controller board and the motor board to learn as much as I can before potentially frying them. Anyone interested in scavaging the useful systems in one of these might be interested. The attached picture, GDcontroller.jpg, shows the controller board at the bottom and the motor board on the right. The 9 pins connected via the ribbon tested as shown in the other attachment, PinTest.txt.
It looks like I might turn the light on by grounding pin 8 (counting left to right at the controller board); make the motor run backward by grounding pin 9 and putting .75 V to pin 6; make the motor run forward by grounding pins 9 and 7 and driving pin 6 again to .75V. Note, I haven't actually tried this yet.
Does it make sense that motor speed might be proportional to voltage at pin 6? Or is my voltmeter averaging a pulsed voltage (maybe 2.5 or 4.9) when it reads .75V?
Plan A is still to bypass that resistor to try to get the allowed torque limit higher. When that doesn't work I'll break in at pins 6,7,and 9, and try to bypass their controller while still utilizing the high power circuits of the motor board.

Not clear on how to attach images; hope this works.


06-07-2006, 10:04 AM
if your try to make it so that no one can get in or open the garage door do what i did and it cost less than $40.00!! what you need is 1=24 volt transformer 1= 24 volt 2 pole contactor like used on a A/C unit and some switches and 24 light to let you know if you left the switch on?1st find the the breaker going to the outlet that powers the to the opener and turn the power offf.BE VERY CAREFUL WHEN DOING THIS AND WORKING AROUND LIVE POWER WIRES!!!!! what you want to do is find the hot(black wire and the white netural wire) remove both from the breaker and netural buss bar and hook the hot to one screw on the bottom left and the netural wire to the bottom right screw. thentake a short section of wire the same size 12 -14 ga wire and hook the hot (black wire to the top left screw and do the same for the white or netural wire for the top left screw. than hook the black or hot wire back to the breaker and the white or netural wire to the netural buss bar.net run at least a 24 ga 4 cond wire to where you want to control the switches.take the transformer and hook it to the same breaker as the opener.i have the 24 ga wires going from 1 side of the transformer(1 wire only) going to the contactor and the other power wire from the transformer going in side to the switch than going back to the contactor.The switch is a spst swith and there are only 2 power (24 volt ) wires off of the transformer. also with the extra 2 wires you can hook to the 2 screw on th back of the opener for the push button and open it from and room you want to?? also if you want to get fancy you can do what i did and installed 2 micro switches on thd door track and lights at the control panel to let me know if the door is open or closed and if i left the power switch on!!cool huh?? with the switch off the contactor is not pulled in and no one can get in even if they have the correct code. i have had mine installed for the last 4 years and no problem with it and think how long your a/c contactor last and the transformer . hope this helps alittle and if you hve any questions or need help e-mail me propwash79@aol.com

06-09-2006, 11:09 PM
For those who may be interested, I was indeed successfull in intercepting the commands, inserting my own from BS2 and controlling motor speed! I almost didn't even try since the chances of it working seemed so remote (not having any kind of circuit diagram for the Genie system controller board).
The BS2 grounds 26V triggers by flipping reed relays as required (simple Pin HIGH and LOW commands to the input side of the relay) and the only other BS2 function used is PULSOUT.
Refering to the earlier attachments showing the 9 wire ribbon connector between controller board and motor board:
(I split the ribbon and unplugged wires 6,7,8,&9 at the controller board and connected them instead to the BS2)
1. Ground wire 8 and light comes on
2. Ground wires 8 and 9 and send PULSOUT 6,800 with Pin 6 connected to wire 6 and motor runs full speed forward.
3. Ground wires 7, 8 and 9 and send PULSOUT 6,800 with Pin 6 connected to wire 6 and motor runs full speed backward.
4. Do PULSOUT 6,200 and motor runs very slow; continuously vary speed min to max with pulse out 200 to 800.

I'll be writing a DO LOOP with a variable for PULSOUT to slowly ramp up the motor speed before I re-install the motor into the "machine". Note: This worked for the Genie "Accelerator" model garage door opener which has a 120VDC motor. So this might be a good option for anyone who wants to build a BS2-controllable 1/2 hp project that runs on standard house electrical.

06-12-2006, 11:13 PM
Just curious if you left, or put in , any current limiting resistors in those "grounding" pins.

Since I'm not quite sure how you hacked the device, I can't say for sure.....but grounding out a voltage will usually heat things up quite quickly....reed relay included.
Wrt the reed relay, you might consider a Solid State one as it will last longer and won't spark and oxidize like normal relays!

Good job reverse engineering though! Great sense of accomplisment! ;)



"Inside each and every one of us is our one, true authentic swing. Something we was born with. Something that's ours and ours alone. Something that can't be learned... something that's got to be remembered."

06-19-2006, 09:14 PM
I've been out of town, so didn't see your post till now, steve. You are right, I'm lucky I didn't burn something up. It is possible that their controller board that I am bypassing did not hard ground the current path to flip the relay, but instead provided some small resistance.

For my reed relays, I put the BS2 output first into a transistor to protect the BS2 pin, so I let the transistor supply the 20 mA on the input side of the relay. The output side of that reed relay then just sinks the wire in the ribbon that goes to the motor board hard to ground. I can then hear the on-board Genie system relays click on. So my BS2 is doubly protected, but I should still consider protecting the Genie motor board relay. I haven't built the permanent wiring yet, so I will take your advice when I do, and see if I can add a little resistance to the Genie relay input side to reduce current and still get it to close.

Regarding the choice of reed relay, I bought some solid state ones from Parallax (Crydom) and they work great for switching on some bright incandescent lights, but thay have a minimum current limit on the output side, so they might not work for driving the motor board relays.

03-19-2013, 06:25 AM
Well done Invariant! It sounds like you've discovered the best way to move the motor by commanding a rate of travel. How then can we get it to go to a position using your connection? I'm interested in getting it to go to three or more positions. And for the sake of the thread I'm probably overlooking the answer and I've probably left out a lot due to my own ignorance so I apologize ahead of time.