Adding a matrix to a keyboard encoder?

[Lilwolf]

Ok, just bought a jukebox... one with about 36 buttons (I think... haven't picked it up yet... but I think its A-Z + 0-1... anyway..)

I don't care at all about gaming... so I was considering buying a 20port cheap keyboard encoder and then try and create my own matrix for the key input.  Can I?

Or after that... How hard is it to hack a keyboard if you don't care about ghosting or others?  should I just hack a keyboard and be done?   I haven't hacked a keyboard before (just a few old joysticks).  I don't think it would be worth my time for 20 bucks and a keywizeco.... unless I had to buy two.

thanks

[Chris]

Hacaking a KB could be just as easy; it depends on the keyboard and what kind of connection it uses.  The last keyboard I hacked, I just de-soldered the connector it hald and was able to solder a pin header in its place for a ribbon cable.  If you have a spare keyboard lying around, rip it apart and see how easy it's going to be to hook up wires to it...

[SirPeale]

If you can solder, hacking a keyboard is dead easy.  For a jukebox project, it'd work really well.

Someone recently posted a howto on keyboard hacking.  They well all out and put it inside a project box.  This tutorial was awesome, with one major thing that I would have changed:

They soldered wires to every lead on the keyboard PCB, then labeled the wires 1-36.  What they *should* have done was label the first of the sets A-H, and the next ones 1-28 (or however many there were).  Using the example I gave makes it much easier to cross-reference a particular keyset.  Let's see how my table skills are holding up...

	1	2	3	4	5
A
B
C
D
E

I'm not sure how to make the lines appear on the table, so just pretend they're there.

[whammoed]

If you decide to hack a keyboard, let me know which one you decide to use.  I may have a map for it already...I have a bunch.

[RandyT]

Here's another option for you:

Use a KeyWiz Eco and wire up 4 more (or however many you need) dual-diode "one-click Shazaaam" buttons.

If you need more info, contact me.

Otherwise, I'm with the "hack a keyboard" crowd.  Jukeboxes are one of the few applications that won't have single problem with it.

RandyT

[Tiger-Heli]

Here's another option for you:
Use a KeyWiz Eco and wire up 4 more (or however many you need) dual-diode "one-click Shazaaam" buttons.

This will work except Lilwolf didn't even want to pay the initial $20 for the Eco.

I have a very detailed page on the theory and how-to (more than you need to know) at http://www.mameworld.net/emuadvice/keyhack2.html, and IMHO, Spystyle has the best "short and sweet" tutorial at http://spystyle.arcadecontrols.com/index79.htm

[RandyT]

This will work except Lilwolf didn't even want to pay the initial $20 for the Eco.

Actually he said:

I don't think it would be worth my time for 20 bucks and a keywizeco.... unless I had to buy two.

Which I took as, paraphrased, unless he needed to buy two, the effort of hacking the keyboard wouldn't be worth it.  I was just saying that it could be accomplished without buying 2 units by just wiring a few buttons with some diodes.

But hacking a keyboard is still a viable option for a jukebox, and those links will certainly help get the job done!

RandyT

[Tiger-Heli]

Re-read the original post and now agree with Randy.

It now sounds like Lilwolf is saying the time to hack the keyboard would be worth more than the $20 for the Eco, unless he had to buy two.

A third option would be to use an Eco and hack a gamepad for the additional 3-4 inputs, but if you're going to hack something regardless, IMHO, you might as well just do it once with the keyboard.

[SirPeale]

Re-read the original post myself, and I definitely stand by my original advice: a keyboard hack would be the best way to get the input.  It wouldn't take much time to map the matrix, AND there would be a vast amount of keys to use.

[Lilwolf]

Time seems to be harder to find then 20 bucks these days.  I'm now steering towards the shazam + diodes method. 

1/2 because I haven't bought anything from Randy yet.   And figuring no matter how good I am.. it will take more then an hour and not look as good.

One other option might be to wire up one of the printer port adapters also.  But I think I am going to put that one off for the same reasons.

But I will pull apart a few of my really old  keyboards and see if it will be trivial (no soldering)... otherwise I'll probably get an Eco board.