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Re: How to program my own keyboard driver?

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On Thu, 19 Sep 2013 12:26:45 -0400, Ruud Baltissen <rbaltissen@gmail.com>  
wrote:

> I received a Commodore 8032-SK [...]
> I attached the original keyboard to the on-board LPT port.

 From a PET schematic, it appears the keyboard works similarly to the C64.

If that's true, then the problem was solved, and more than once:

http://symlink.dk/projects/c64key/
http://www.vesalia.de/e_keyrah.htm
http://www.waitingforfriday.com/index.php/C64_VICE_Front-End
http://www.go4retro.com/products/ckey/

It could be possible for those to work or be adapted to your keyboard.

I'm surprised you're not familiar with these Ruud since it appears
you've posted a schematics for Commodore C64 like device.

I would start by comparing the keyboard connector lines of the C64
and 8032-SK.  I.e., do they have the same number of pins?  If not,
does the C64 have more than enough of both input and output lines?

C64
9 rows 0 through 8
9 columns A through I

PET
7 (or 8) rows (?) A through H (or J)
10 columns (?) 1 through 10

The C128 seems to be 8x11, so maybe an adapter for it would work.

> [keyboard TSR and/device driver for DOS]

Are you still interested in a DOS device driver when so
many keyboard adapters are available?

If so, you could look at :
  "Chapter 8. Writing an Installable Device Driver"
of IBM's "PC DOS 7 Technical Update" manual:
http://www.redbooks.ibm.com/redbooks/pdfs/gg244459.pdf


FYI, the C64 keyboard is just a matrix of input and output lines, where
the input lines are scanned one at a time.  I have a bunch packed up
in the basement somewhere...  If a key is pressed, an output line will
be active.  This usually requires one chip to decode a binary value to
a single line to implement scanning, and another chip with multiple
input lines which are read.  The first is a demultiplexer, e.g., a BCD
to decimal decoder or 1 of 8 decoder, etc.  The first chip is usually
fed by a few pins on a microprocessor with an incrementing output value.
A counter chip can also drive it.  The second is usually an addressable
latch, i.e., memory or I/O mapped with value readable by a microprocessor.
There are also standard logic chips for keyboard scanning for the chip
series Commodore used, e.g., 6526.


Rod Pemberton

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Thread

How to program my own keyboard driver? Ruud Baltissen <rbaltissen@gmail.com> - 2013-09-19 09:26 -0700
  Re: How to program my own keyboard driver? JJ <duh@nah.meh> - 2013-09-20 06:02 +0700
    Re: How to program my own keyboard driver? Ruud Baltissen <rbaltissen@gmail.com> - 2013-09-20 03:07 -0700
  Re: How to program my own keyboard driver? Ross Ridge <rridge@csclub.uwaterloo.ca> - 2013-09-20 00:03 -0400
    Re: How to program my own keyboard driver? Ruud Baltissen <rbaltissen@gmail.com> - 2013-09-20 03:38 -0700
      Re: How to program my own keyboard driver? Ross Ridge <rridge@csclub.uwaterloo.ca> - 2013-09-20 09:19 -0400
  Re: How to program my own keyboard driver? "Rod Pemberton" <dont_use_email@nohavenotit.com> - 2013-09-20 00:53 -0400
    Re: How to program my own keyboard driver? Ruud Baltissen <rbaltissen@gmail.com> - 2013-09-20 03:42 -0700
      Re: How to program my own keyboard driver? Ross Ridge <rridge@csclub.uwaterloo.ca> - 2013-09-20 09:31 -0400
      Re: How to program my own keyboard driver? "Rod Pemberton" <dont_use_email@nohavenotit.com> - 2013-09-20 15:07 -0400
        Re: How to program my own keyboard driver? Ross Ridge <rridge@csclub.uwaterloo.ca> - 2013-09-21 11:56 -0400
  Re: How to program my own keyboard driver? "Bill Buckels" <bbuckels@mts.net> - 2013-09-20 20:21 -0500

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