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Main => Main Forum => Topic started by: Nightmare03 on March 13, 2004, 10:01:13 am

Title: Keyboard hack + Keyboard
Post by: Nightmare03 on March 13, 2004, 10:01:13 am

Hey,

I use a keyboard hack for my arcade controls, but the motherboard i have only takes a AT keyboard and the keyboard hack im using is a ps/2 keyboard so i just soldered it onto the board and it works fine, but the thing is i have also soldered on a normal keyboard aswell... i cant have them both working at the same time anyideas how i can?? Also, both the keyboard hack and keyboard allow me to detach the wire from them so i basically have to detach the wire from the keyboard hack to use the keyboard and detach the keyboard to use the keyboard hack.

I was wondering if there is a way to make them both work at the same time, or if putting a switch on the +5 on the keyboard to allow me to cut the power to that one instead of having to disconnect it.

Any help will be appreciated,

Nightmare

Title: Re:Keyboard hack + Keyboard
Post by: OSCAR on March 13, 2004, 10:12:12 am

They can't be spliced directly together, as you have found out already.  A circuit was developed to allow simultaneous keyboards and can be found here:  http://home.t-online.de/home/stephan.hans/tricks.htm.

This link was found under the "Interfaces" heading right here on the BYOAC site.

Title: Re:Keyboard hack + Keyboard
Post by: SirPeale on March 13, 2004, 10:24:32 am

You soldered it?  Why didn't you buy a $1.00 AT to PS/2 adaptor?

Title: Re:Keyboard hack + Keyboard
Post by: Zeitgeist on March 13, 2004, 10:33:58 am

Here's Jay's Simpler Circuit.
I have built several keyboard splitters with my own variation of his AT design (PS2 as opposed to 5 pin Din).
It works great.

Title: Re:Keyboard hack + Keyboard
Post by: Zeitgeist on March 13, 2004, 10:51:05 am

Here's my adaptation of Jay's Splitter, redesigined for use with PS2 keyboards in case anyone is interested.
All you need is:
1 male 6 pin mini din plug (or cut a 6' PS2 extension cable)
2 female mini din plugs
1 4066 IC  (Quad Bilaterial Switch)
1 4093 IC (Dual NAND Trigger)
Some micro wire & a project board & box

BTW these can be daisy chained without any adverse effects.

Remember however that for a price there are two terrefic interfaces out there that will do a much better job than any old keyboard could.
With the blocking & ghosting issues and the time it takes to map out the matrix, keyboard hacks are hardly worth the trouble, unless you like the challlenge.
Just my 2 cents...
On the other hand I do have two stand alone panels that have hacks in them & work great except when all six buttons for both players are pressed simultaneously & both joystick are at a vertical.
Naturally they don't use the default MAME keystrokes.

Hope this helps.
Z

Title: Re:Keyboard hack + Keyboard
Post by: Nightmare03 on March 13, 2004, 11:23:32 am

Thanks for the advice but i dont really wanna make a entire circuit... Is it possible to just cut off the +5v to the keyboard, thus cutting off its power and then disableing the keyboard?

Title: Re:Keyboard hack + Keyboard
Post by: RandyT on March 13, 2004, 06:34:55 pm

Quote from: Nightmare03 on March 13, 2004, 11:23:32 am

Thanks for the advice but i dont really wanna make a entire circuit... Is it possible to just cut off the +5v to the keyboard, thus cutting off its power and then disableing the keyboard?

All you need is a DPDT toggle switch and the 2 lines you need to switch are CLOCK and DATA.  Leave the GROUND and +5v hooked up for both devices.

RandyT

Title: Re:Keyboard hack + Keyboard
Post by: Nightmare03 on March 14, 2004, 07:23:21 am

Thanks, ill give it a try later ;D