Step 4: Keyboard Hack

I had half way done with the keyboard hack because six months before the starting of this project I built a control panel prototype just to know if it would work.

I got an old PS keyboard and removed the printed circuit board (PCB). Then I soldered a wire to each pin of the PCB (if I had to do it again, I would use a ribbon cable instead). With the maylar and the keyboard layout I was able to determine the definition of each key.

I needed to handle 24 keys:

4 keys for player 1 joystick
4 keys for player 2 joystick
6 keys for player 1 buttons
6 keys for player 2 buttons
1 key for escape button
1 key for insert coin button
1 key for one player start
1 key for two player start

Most games will work OK with this setup.

One of the most difficult things with the keys selection was to avoid the "ghosting" and "blocking" got in some cases:

What this means:

Ghosting: when you press 2 keys you got a third
Blocking: pressing certain keys combinations they blocks others

I created a reference sheet as a helper to choose the right keys as you can see in the picture.
<p>Really nice build. I am planning to do something similar too. I am a programmer, and I also want to make my own front end. Could you please give me some info about how you did it? ( I do know vb6 as well)</p>
<p>Hi JackM36,</p><p>I read the gamelist file generated by Mame and then displayed it in the screen<br>When the user choose a game, call the mame.exe with the game name as parameter along with other ones (like fullscreen display, etc). Basically what I do is to call command line mame.exe with parameters, with shellexec32</p><p>Anyway, as I mention before, there is a much better frontend than mine called MaLa which has many cool features.</p><p>Thanks for your comment and good luck.</p>
Thanks for your reply, that was very helpful. I know about MaLa and other cool front ends, I am just the kind of person that like to do things myself. I also enjoy the challenge of doing things I never tried before! :)
Hi Crusso. Great instructable. You can use a router to cut a hole in MDF and get a smooth edge for the bezel. If you setup a jig with a straight rule to control the router its actually quite easy. Youtube has a lot of videos and this is how I learnt.
Hi WildMan, <br>Thank you for your comment, <br>I have a router now but not at the time i built this arcade machine. You're right, it would be much better with a router. <br> <br>Regards.
Great instructable, Carl..<br>Here is mine I am making..<br><br>It is a MIME, PINBALL..<br>
whats mime
Sorry, it suppose to say:<br>Mame<br><br>Multiple Arcade Machine Emulator
thanks for the info
Wow, that looks really cool. You should post an instructable or at least a video when you're done. It looks amazing,
Awesome gonna build asap <br>
thats cool might make this for the kids put there xbox 360 in it
Awesome job, Carlos. You did very well making this from scratch, without blueprints.<br><br>I would be a little concerned about using fiberboard, if your operating environment has moisture. That's not a problem for you maybe, but on a basement floor (even if it is &quot;dry&quot;) it would be an issue. Fiberboard just wicks up any moisture it can get. Rubber feet will help, raising it off the floor.<br><br>I would love to build one of these, but in a cocktail format cabinet.
I totally agree with you. The MDF is not the best kind of wood to do this... I'm currently building a new pacman-style machine, with other kind of multi-layer wood (i don't know how to spell it in english :) like this one:<br><br>http://centrocarpintero.com.uy/imagenes/placas/multiplaca%202.jpg<br><br>Thank you for your comment, hope to hear about your cocktail cabinet soon!
If that saw blade driven by a drill lol
That's no saw blade, it is a sanding disc!
that's right scottinnh :)
Im really new to this whole thing. Do you think you could some how explain exactly what to do for a fellow amature? Brilliant project by the way.
I dont get it ether
I don&acute;t understand your question, please let me know how can I help you.
Sorry ignore that comment I skipped the keyboard step. But would you make a list of all the games?
Hi!<br>For this project I installed mame 0.84. There are thousand games supported in this version, but i recommend you to visit www.mame.net to get the latest version much newer than this one. And if you wish to install a frontend to launch mame in a friendly fashion, go to www.malafe.org.<br><br>Thanks for your comment.
thats brill ! <br>how much did that cost you to make?
hi, thanks.<br>you can see the complete cost list at http://www.carlosrusso.com/arcade/spanish/costs_sheet.htm<br><br>Thanks for your comment.
I don't suppose you'd post your marquee artwork as a downloadable file? And did you print it on regular paper or use some sort of transparency?
Not to be a stickler but that isn't a neon light. It's a florescent light. And a 13w florescent light is the same output as a 60w incandescent light bulb. But over all this is a great instructable!!!!!!!!!!!!!!!!!!!!!!
Hi Mikey, thanks for your comments. Yes that's right, it's a fluorescent light.<br>I live in Uruguay, here we have 220v AC. This bulb has a little transformer, so the bulb works with only 12v. Best regards! Carlos.
Yea I'm a electrician by trade (Many other trades under my belt too LOL) and I've dealt with a lot of voltages ranging from .01 vdc to 10k. a lot of the electronic ballast's for florescent fixtures take multi voltage inputs. I've been replacing most of my projects with LED so I don't have to change out builds as much. Good job on the project!
Might include a warning that #1 the input to it is 125 VAC and the output to the bulb (via the ballast) is around 8k-10k VAC so a electrical shock warning to all the users.
great work
Wow! very nice. I plan on doing 1 soon. great project. thanks for shareing
Thank you!
Thank you very much! I am just an amateur in woodworking, but I like a lot to build things and enjoy the whole process.<br><br>Regards!<br>Carlos.
You mentioned the image was flipped in the tv and did not look right. Just fyi there's a plug inside your tv called the yoke connector that connect to the large mess of windings on the back of the tube. There are only 4 wires on this connector so its easy to find, and it goes straight to the main board inside the tv. The four wires basically control the height and width of the image, and if each correspoding pair is reversed, they will reverse the image. Flipping it horizontally AND vertically will make the screen perfectly upsidedown. Your supplier may have only flipped it vertically which would have accounted for the &quot;mirrored&quot; image (which many of the old arcade cabinets used along with an actual mirror to reposition the video screen to a more natual position, while keeping the tv itself tucked away where there is more room).
Yes, that's right. The supplier did it wrong the first time and I went back and ask him to fix it.<br>He told me what you're mention, about the wires. He did it this way.<br><br>Thank you for your comment.
Wow, I am thoroughly impressed. I work as a gameroom technician for an arcade and I have to say your craftsmanship surpasses most of the arcade games that I work on that are from professional companies. My favorite part is the pull out keyboard tray, well hidden!
I like the finished product.<br><br>I especially like your keyboard controller hack.<br><br><br>You said &quot;Most of the older TV's in my country has composite (RCA) inputs and not s-video&quot;<br><br>Just so anyone trying this knows, there are MANY many many s-video to rca cables available. In fact, my last 2 video cards came with them, in the box. You can even hack one together with an old p/s2 cable, and an rca jack. Just a matter of hooking up the correct pins.
Hi ironsmiter,<br>thank you for your comment. I have another keyboard hack much simpler to be used on a 1 player arcade. I made it by hacking a keypad. Is much simpler and fits in a very little plastic cabinet.<br><br>I tried with many different s-video to rca cables but I got very poor results, that's why I decided to buy the xga unit.<br><br>Thanks!<br>Carlos.

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