Well, I'm including
a couple pictures (I hope you can view them) that might help a little on
how this controller works. One is a color photo of the keyboard
interface. It shows the front side of the keyboard mainboard
attached to a piece of wood along with the connector strip. On the
back side of this mainboard is a strip that looks like the traces on the
edge of a PCI card. This strip is where the 30 wires from the ribbon
cable attach. I don't know if you have ever been into a modern keyboard,
so I will try to give you a quick take on it. Note: There is no standardization
for the Way the matrix is laid out. One brand of keyboard may be
totally different from another even though they use the same IO chip.
As the caps lock, num lock, and scroll lock LED's are powered by +5 volts
it is important to not connect those lines to the buffer as this will permanently
damage your motherboard. I used a keytronics keyboard for this project.
If you use another brand of keyboard you will need to trace the matrix
out yourself. Not a hard process but it will take a little time.
You'll defiantly understand it better afterwards.
The mainboard you see
in this picture connects to 2 pieces of
mylar. The mylar has traces and pads on it that look like the surface
of a printed circuit board. Each of the 30 traces (15 each piece) passes
through several pads on the mylar. This is what makes up the matrix.
Without the matrix each key would need two wires ran to it creating a huge
mass of spaghetti. All the pads on one piece of mylar line
up with the pads on the other piece, so that when the key above it is pressed
it mashes the pads together and makes a contact/closes a circuit. Okay,
now remember that each trace passes through several pads. for
example lets look at traces 5 & 10. Trace 5 is on the bottom sheet
of mylar and it starts out at the pad for the F6 key. It then goes on to
F5, F4, ESC, G, H, ', "up arrow", 0, and period on the number pad.
Trace 10 on the top sheet starts at ESC, 1, ~, TAB, Q, A, then Z.
Now if you look at the second picture
this is part of my matrix map, (I tried to get it all in the scan but it
makes too bit of a file) you will notice that the only place on the matrix
that trace 5 and trace 10 cross is the ESC key. So, let's say we
want to rig our "reset" button so that it will "escape" out of a game
back to the menu. All we need do is wire the 2 wires from that button
to the connector block on connector 5 and 10. Now every time you
press this "reset" button it's just like pressing ESC. That's it
you just wire buttons and joysticks to whatever keys you want like 4 and
11 for F1 or 4 and 8 for the left CTRL key.
Now as I stated on Daves
board, I use Arcade Menu as a front end for all my EMU's.
Mame, Callus, System 8 & 16, Mame/P, Cine, Rage, Pitfall2, EMU, etc.
All these emu's will launch from arcade menu to full screen dos and then
back. Enter selects, escape exits, and the up and down arrow keys
will scroll through the menus. So, if you map your player one joystick
to mame standards you will have all four of the arrow keys, the Left CTRL
and ALT keys. If you map reset to ESC and Select to ENTER you will
have all your menu controls on the control panel with no need for a keyboard
hanging on the cabinet. The rest of the keys don't really matter
much, but try to stay away from windows combos like ALT and TAB or ALT
and P as some EMU's use this as a pause. I say this because if you
are playing even a two player game and your bomb button is mapped to the
ALT key and player 2's fire button is mapped to the TAB key and you drop
your bomb at the exact second player 2 fires. Suddenly another window pops
up and your Emu dos screen dies in the process. :-(
IT's best if you map
both the ESC key and the CTRL keys but not both to player keys. I
have CTRL mapped to player one fire and ESC mapped to the reset button.
This way it's not likely that they will both be pressed at the same time
by accident. You want these to keys because when it comes time to
shut down your machine you either have to have a mouse,(remember I'm using
a track mouse, but not wiring the buttons to anything since all the Mame
mouse games let you map keys for fire) or a keyboard attached. What
keys on the keyboard do you toggle to get the start menu? CTRL/ESC
(Fire button/reset).
Whew, I bet you weren't
expecting a book. ;-)
As for the coin slots
I using a real arcade coin door complete with coin switches. The
coin switches are just little switches with a piece of wire attached to
them that the coin hits as it slide down the slot. When it hits the wire
it momentarily closes the circuit, just like the fire buttons do.
Wiring them to the 3 and 4 keys, (Don't forget some emu's like System 16
require player 2 to be started with a separate coin button) Was as simple
as connecting the coins switches to 3 & 12, and 3 & 13! As
I said some games like Centipede have a little problem with the coin insertion,
but I figure I might hide a small button someplace handy that can be used
to insert a coin for those problem games. I just think that the idea
of having to put in quarters adds to the nostalgia.
--- Thanks Shadow (saint)