DOS ain't dead

International keyboard support (Developers)

posted by marcov, 22.01.2023, 14:19

> On the keyboard side there is the KEYB.COM program. From what I can tell
> when you use KEYB it just fixes or replaces the standard BIOS handling,
> converting scan codes to something different from the default. It also
> allows for some shift/meta type operations to generate additional
> characters. But ultimately, the output is still going to be a value from 0
> to 255 representing a character, and hopefully the matching code page for
> the video display is resident. Otherwise, you get the correct character
> but an incorrect display.
>
> Does this sound about right?

That sounds all about right. The kbd must generate multi character sequences, and the display system must support writing those.

Additionally, quite often the display system requires such sequences to be written in one sys/int call. (so if the intermediate programming breaks them up it can also cause artefacts).

And of course anything that does character positioning must be fixed because new position is no longer old position + bytes written. etc etc.

Complete thread:

• International keyboard support - mbbrutman, 21.01.2023, 21:44
  • International keyboard support - marcov, 22.01.2023, 14:19
  • International keyboard support - tom, 22.01.2023, 18:06
  • International keyboard support - Laaca, 22.01.2023, 21:55
    • International keyboard support - mbbrutman, 22.01.2023, 22:46
      • International keyboard support - Laaca, 23.01.2023, 00:20
      • International keyboard support - bretjohn, 23.01.2023, 18:12
        • International keyboard support - mbbrutman, 23.01.2023, 23:51
          • International keyboard support - bretjohn, 24.01.2023, 21:10
        • International keyboard support - tom, 12.02.2023, 18:39
          • International keyboard support - bretjohn, 13.02.2023, 15:35
            • International keyboard support - tom, 13.02.2023, 18:36
              • International keyboard support - bretjohn, 14.02.2023, 04:51
            • International keyboard support - tkchia, 13.02.2023, 20:13
              • International keyboard support - bretjohn, 14.02.2023, 05:05
      • International keyboard support - tom, 14.02.2023, 12:17
        • International keyboard support - tom, 15.02.2023, 13:19
          • International keyboard support - marcov, 15.02.2023, 18:14
            • International keyboard support - tom, 15.02.2023, 21:31
              • International keyboard support - mbbrutman, 18.02.2023, 03:17
                • International keyboard support - Aitor, 06.03.2023, 01:09