PS/2 keyboard emulation

[CumQuaT]

Hi all,

I'm having a look into a project that takes input from a circuit (push buttons) and sends it through to a PS/2 cable that can be plugged into the keyboard port of a PC. I'm trying to get the push buttons in the circuit to send the data of certain keys from the keyboard. For example, when I press one push button it sends a lower case "a" to the computer, and when I press the other push button it sends a space.

Has anyone had a play around with this before? I've been having a fiddle with using a PIC for it without much luck...

Any help would be great.

[bethr]

Has anyone had a play around with this before?

I did ! (-Played-) several yrs ago....
look at this i dont remember but it's part off a bigger program... any way I hope you can find it useful...

 'ps2 emu-sw betomax
 DEFINE SHIFT_PAUSEUS 15
 char        var Word  'character
 datpin      var porta.0   'Keyboard Data ' 10k pull up
 clkpin      var porta.1   'Keyboard Clock ' 10k pull up
 col         VAR   BYTE     ' Keypad column
 row         VAR   BYTE     ' Keypad row
 key         VAR   BYTE     ' Key value
 delayer con 100    'delay btw chars
 CMCON = 7
 trisa =0
 datpin = 1
 clkpin = 1
 OPTION_REG.7 =    0        ' Enable PORTB pull-ups
 h var word : h = %11001100110
 o var word : o = %11010001000 
 l var word : l = %11010010110
 a var word : a = %10000111000
 b var word : b = %10001100100
 c var word : c = %11001000010
 d var word : d = %10001000110
 uno var word  : uno =  %10000101100
 dos var word : dos =  %11000111100
 tres var word : tres =  %10001001100 
 cuatro var word : cuatro =  %10001001010
 extcode var word : extcode = %10111000000 'e0
 berak var word : berak  =%11111100000 'f0
 intro var word : intro = %11010110100 '5a

Start:

 GOSUB Getkey ' from switch / keypad

 Select CASE Key ' wich key ??
  case 1
   char = uno : GOSUB sendchar : pause 500
  case 2
   char = dos :GOSUB sendchar : pause 500
  case 3
   char = tres :GOSUB sendchar: pause 500
  case 4
   char = cuatro: GOSUB sendchar: pause 500
  case 5
   char = a : GOSUB sendchar: pause 500
  case 6
   char = b: GOSUB sendchar: pause 500
  case 7
   char = c : GOSUB sendchar: pause 500
  case 8
   char = d :  GOSUB sendchar: pause 500
  case 9
   char =h:GOSUB sendchar: pause 500
     case 10
   char =o:GOSUB sendchar: pause 500
  case 11
   char = l:GOSUB sendchar: pause 500
 END SELECT
  pause 500
  goto start

'actually make ps2 tx !

sendchar:
  shiftout datpin,clkpin,0,[char\11] : pauseus 50
  shiftout datpin,clkpin,0,[berak\11] : pauseus 50
  shiftout datpin,clkpin,0,[char\11]: pauseus 50
  return

[CumQuaT]

This looks neat! I'll have a crack at it!

I was wondering though, do you have more of the keyboard codes? The application I plan on using will make use of 21 keys in the end...

[mackrackit]

Did you try searching the forum? Found this.
http://www.picbasic.co.uk/forum/showthread.php?t=2736

[CumQuaT]

Yeah, I had seen that, but it is dealing with the exact opposite of what I'm trying to do. I'm not trying to interface a keyboard to a PIC.

[mackrackit]

Yeah, I had seen that, but it is dealing with the exact opposite of what I'm trying to do. I'm not trying to interface a keyboard to a PIC.

Hmmm. Did you read the whole thing? Guess not.

[CumQuaT]

When scanning a forum for similar topics, no-one reads each thread in it's entirety.

I'll have a look now you've drawn my attention to it. Thanks for the link.

[mackrackit]

When scanning a forum for similar topics, no-one reads each thread in it's entirety.

I knew I was doing something wrong

[Archangel]

When scanning a forum for similar topics, no-one reads each thread in it's entirety.

Nobody's ever always or never. I usually do.