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Main => Main Forum => Topic started by: cnsf on May 20, 2015, 02:11:27 pm

Title: Q*bert knocker for MAME Cabinet - help needed
Post by: cnsf on May 20, 2015, 02:11:27 pm
I'd like to add a real Q*bert knocker to my cabinet but have found very little current information on how to get it done and need some help.  Here is what I bought and know (I'm also not a newbie by any means and have already done a lot of research on this - I'm not a programmer, though): 1) bought Q*bert knocker assembly from Twisty Arcade 2) bought PACDRIVE from Ultimarc.  I know I need to get MAME to send a LED signal to the PACDRIVE to trigger the solenoid.  I know I can hook up either a 12V (from the PSU) or 5V (from the PACDRIVE) to the solenoid, but not sure which is the right one.  The ground comes from the USB connection in the PACDRIVE.  I know I can run LEDUTIL.exe at Windows Startup (using Windows 7 Ultimate) to get a message from MAME "knocker0", but not sure what LED is triggered by that or if I need other software to pick that up and remap it to an LED.

Any help in creating a step-by-step for this would be very much appreciated.

My cab is at http://www.notrica.com (http://www.notrica.com).  I will be adding a 45 degree angled joystick between the P1 buttons and the spinner to play Q*bert and Congo Bongo.  The knocker would just make the cab truly awesome. (Lightguns already added btw and had to swap out the monitor for an LCD to get them to work).

Thanks in advance!
Title: Re: Q*bert knocker for MAME Cabinet - help needed
Post by: yotsuya on May 20, 2015, 02:20:53 pm
What is the voltage requirement for the solenoid coil you have? I think the original Q*Bert used 30v. 12v and 5v would be weak.
Title: Re: Q*bert knocker for MAME Cabinet - help needed
Post by: cnsf on May 20, 2015, 02:32:39 pm
It's a A-5195 Gottlieb coil, from what I can see. I can only find that it is a 12ohm coil.  I wonder if 30V would blow it.  I'd also have to get separate power for it if it's more than 12V.
Title: Re: Q*bert knocker for MAME Cabinet - help needed
Post by: yotsuya on May 20, 2015, 02:37:02 pm
It's a A-5195 Gottlieb coil, from what I can see. I can only find that it is a 12ohm coil.  I wonder if 30V would blow it.  I'd also have to get separate power for it if it's more than 12V.

A-5194 is a 12v coil. Here's a video showing A-5195 with a 30v source:

https://www.youtube.com/watch?feature=player_embedded&v=9Lh_FVGCfa4 (https://www.youtube.com/watch?feature=player_embedded&v=9Lh_FVGCfa4)
Title: Re: Q*bert knocker for MAME Cabinet - help needed
Post by: cnsf on May 20, 2015, 02:39:20 pm
Cool.  So, let's say I get a separate power brick to give it the 30V it needs, what do I do on the software side to get the Q*bert message from MAME to the knocker?

Also, do you have a suggestion for a 30V power source?

Thanks for your time on this!
Title: Re: Q*bert knocker for MAME Cabinet - help needed
Post by: lamprey on May 20, 2015, 02:41:26 pm
I don't have any direct information for you. But, a knocker is pretty common for Virtual Pinball machines. So, you may find more information on a pinball site.
Title: Re: Q*bert knocker for MAME Cabinet - help needed
Post by: yotsuya on May 20, 2015, 02:47:36 pm
Cool.  So, let's say I get a separate power brick to give it the 30V it needs, what do I do on the software side to get the Q*bert message from MAME to the knocker?

Also, do you have a suggestion for a 30V power source?

Thanks for your time on this!

Actually, I'd just buy a A-5194 12v power coil.

http://www.marcospecialties.com/pinball-parts/A-5194 (http://www.marcospecialties.com/pinball-parts/A-5194)

 :cheers:
Title: Re: Q*bert knocker for MAME Cabinet - help needed
Post by: cnsf on May 20, 2015, 02:52:33 pm
I am hoping to get the same knock that was in a Q*bert machine.  Would the 12V knocker do the trick?  I already have the A-5195 knocker assembly ready to mount.

What about the software?  Do I need to use MAMEHooker or has MAME been updated enough to support LED mapping (outside of the standard three LEDs)?
Title: Re: Q*bert knocker for MAME Cabinet - help needed
Post by: ndiniz on May 20, 2015, 06:54:44 pm
What would a knocker be used on a MAME cabinet for? I was only aware of a knocker being used on pinball machines to indicate a free game, whether it be by match or by replay.
Title: Re: Q*bert knocker for MAME Cabinet - help needed
Post by: blacketj on May 20, 2015, 07:11:54 pm
Here is an old thread with lots of info on why and how.

http://forum.arcadecontrols.com/index.php?topic=109029.0 (http://forum.arcadecontrols.com/index.php?topic=109029.0)
Title: Re: Q*bert knocker for MAME Cabinet - help needed
Post by: cnsf on April 08, 2016, 02:40:27 pm
What would a knocker be used on a MAME cabinet for? I was only aware of a knocker being used on pinball machines to indicate a free game, whether it be by match or by replay.

The original Qbert had a knocker in the cabinet that activated when Qbert jumped off the side.
Title: Re: Q*bert knocker for MAME Cabinet - help needed
Post by: cnsf on April 08, 2016, 02:46:34 pm
Here is an old thread with lots of info on why and how.

http://forum.arcadecontrols.com/index.php?topic=109029.0 (http://forum.arcadecontrols.com/index.php?topic=109029.0)

I got the knocker working.  Details here: http://www.notrica.com/qbert.shtml (http://www.notrica.com/qbert.shtml)

I now have an issue with MAMEHooker and running consoles (Coleco, Sega Genesis, Intellivision) through the new version of MAME that combines the MESS drivers.  I narrowed down the problem to MAMEHooker (every console works when MAMEHooker isn't running).  When launching the consoles, I get a long series of dialog boxes that need to be x'ed out.  Once done, the console is running in the background and has to be alt-tabbed to.  I've tried a number of things to isolate mame executables and inis with no luck (including specifying the directory and executable in MAMEHOOKER separate from the standard MAME executable).  MAMEHooker picks up the MAME executable when running, regardless of location.

Is there any other option to capture the knocker activity in Q*Bert and run it through PACDrive besides MAMEHooker?

Title: Re: Q*bert knocker for MAME Cabinet - help needed
Post by: cnsf on January 07, 2021, 09:53:30 pm
So, the solenoid kept burning out on me using the 30V and A-5195 coil.  I updated the knocker to a A-5194 coil and assembly and used a 12V 2A power source (should have done that in the first place as recommended).  I can't tell the difference between knocks.  Still gives you a bit of a scare.

Haven't had burnout problems (yet) with the new power source.

I also adjusted the MAMEHooker timing to "wat 50"
Title: Re: Q*bert knocker for MAME Cabinet - help needed
Post by: mahuti on January 08, 2021, 09:24:07 am
I picked up one of these awhile back and wired it into my system. Basically the same as you have now.
 https://www.arcadeshop.com/i/1125/q-bert-knocker-assembly-with-12v-coil.htm

I'm on Linux so I didn't use Mamehooker. I worked with the author of LEDSpicer to add support for knockers in his software. We decided to default knockers to 50ms If I recall correctly. Though I went through a few fuses in testing, its been running for the last few months without a problem.

I tried looking into a hardware solution to limit the runtime of the solenoid using a transistor (and other stuff)  but I'm not good enough with electronics to figure out the right parts on my own. Still rattling around in my head though.