Keypad Question

Vee24 · 06-19-2005, 01:57 PM

I did some reading on how to hack a keyboard and map the matrix. Then I found this keypad which is already mapped and has it's own matrix. http://www.allelectronics.com/cgi-bi...-24&type=store

Is this like a mini keyboard with it's own keyboard controller?

How would I use something like this and what type of nine pin connector is that in the specs? Thanks for the help.

Jahntassa · 06-19-2005, 03:16 PM

It's basically the keypad itself. You'd still need to match it up with a keyboard controller or something... The matrix just shows which pins 'short' when you hit the key...

mushin · 06-19-2005, 03:20 PM

That is like a mini keyboard _without_ a controller.

The big benefit to hacking a keyboard is that it's simple plug & play. If you wanted to use that keypad, you'd have to build your own controller or interface though the parallel port and have purpose built software to take whatever action you wanted on keypresses.

Stick with the keyboard. You don't need to map the whole matrix, just the keys you want to use.

Jahntassa · 06-19-2005, 06:31 PM

Well, if he wanted to use that keypad, he could use it with a keyboard that he hacked up. He'd still have to map the matrix of the keyboard he pulled apart, and then work out which keys the 16 keys on the keypad would represent.

A lot easier than building his own controller..

Vee24 · 06-19-2005, 07:18 PM

Thanks for all the answers guys, I have another question. After I hack this keyboard, can one switch be used for hotkeys like Ctrl + Alt + R? Is it possible to put three leads from the controller on one switch? Or would a macro program have to be running all the time?

...Actually two questions: Would you do the serial port button board with girder, or the keyboard hack? I would like to do it without girder or macro software running if I can.

Jahntassa · 06-19-2005, 10:07 PM

Not sure about the three at once.. I guess it would depend on the keyboard's matrix to see if you can do it with easy wiring.

A USB keyboard I tested had a few shortcuts actually in it, only the usual, like Ctrl+C, Ctrl+V

rdc_3200 · 06-19-2005, 10:47 PM

well, what I've been doing for a while is the keyboard hack...I got an old joystick(one of the flight simulator ones with lots of buttons) and hooked up those buttons to the keyboard controller. I had to map out the keys and figure out which characters I wanted each button to represent. I found a program to controll winamp via keyboard buttons. (like to play I'd press 'p' and to go to next track 'n'...etc.) It's been a handy and cheap solution to controlling my carputer. To do the keyboard hack it just required an old keyboard, the joystick, and a free program from winamp's site.

However, I recently found Microsoft Streets and Trips 2005 with a GPS reciever for really cheap. I installed it and have been trying to controll the GPS. The problem I'm having is that I can't type certain characters because all they do is controll functions in winamp. So, I am going to have to look into the whole serial port controller/girder.

Vee24 · 06-20-2005, 02:24 AM

I also read that some people have blown their motherboards up while trying to map it. So I don't want to try the three connection thing till I find something about it. I've been searching all day and can't find anything about modifier keys.

rdc_3200 · 06-20-2005, 07:44 AM

what exactly do you mean by 'modifier keys?'

evandude · 06-20-2005, 08:17 AM

would it by any chance be useful to you to have the keypad output serial data? (should interface very easily with girder)

I made a serial keypad for my carPC last year, and it was simply a microcontroller reading a matrix key arrangement and outputting serial data accordingly... I think that it would probably work directly with your keypad setup, or at least with minor modification... let me know

Vee24 · 06-20-2005, 09:11 AM

rdc..... CTRL and ALT are called modifier keys, that's what I learned while reading about the keyboard hack. I want to be able to have a one button touch for the hot keys in Centrafuse.

evandude, I am still considering Girder, I've read about the button interface. Just trying to decide if a keyboard hack would be better. If the keyboard hack can be done using two and three key combinations without having a program running in the background like Girder, I may like that option better.

evandude · 06-20-2005, 09:19 AM

i don't think you'll be able to do multiple key presses in hardware like you are thinking. you would just be shorting different lines of the matrix together, which will probably render it unusable. the way to do it would be to make something like my serial keypad board, except have it transmit on the PS/2 bus (making the computer see it as a keyboard) instead of via serial. I have also done PS/2 transmission, I don't know how hard it would be to hack my design for PS/2, but it *might* be easy... i suppose whether or not I would want to tackle it would depend on if anyone else is interested in using it...

Vee24 · 06-21-2005, 06:17 AM

I think the keyboard hack is the easiest solution for me. I found micro switches that are 3/16" wide, so I can get three of them under one button to push for the hotkeys in Centrafuse. I'll hack an RF keyboard to avoid running wires thru the steering column.

Jeep · 06-21-2005, 06:25 AM

X-Keys is programble keybords, maby a way to go. http://www.x-keys.com/xkeys.php

Gobby · 06-21-2005, 06:31 AM

I've hacked up a keyboard controller to do my steering controls, only four options but it works really well.