dbrooks@penge.osf.org (David Brooks) (01/02/91)
I was trying to do something with 8-bit keyboard input, and use the ALT key to signal "hi-bit on" I'm reading with Bconin. The general idea was to see if the translated character is zero; if so, and kbshift indicates ALT, I would re-translate the scancode using the standard keyboard mapping tables and plug in the top bit. Mostly, this works fine. But the keys in the top row, between "1" and "=", get 0x76 arbitrarily added to their scancodes before being returned to me. Of course, once I knew this I could compensate for it. But does anyone know the rationale for dickering with something as basic as the scancode? It's the 11/86 ROM, if it matters. -- David Brooks dbrooks@osf.org Systems Engineering, OSF uunet!osf.org!dbrooks In Memoriam: Chris Naughton, aged 16, killed by a drunk driver Dec 22, 1990
apratt@atari.UUCP (Allan Pratt) (01/03/91)
dbrooks@penge.osf.org (David Brooks) writes: >...the keys in the top row, between "1" and >"=", get 0x76 arbitrarily added to their scancodes before being >returned to me. That's not arbitrary; it's part of the VDI spec, which is really just a codification of the behavior of the IBM PC keyboard/scancode characteristics. I don't know WHY it is, but the keys from 1 to = are defined to return scan codes 0x78 to 0x83, and that's just the way it is. ============================================ Opinions expressed above do not necessarily -- Allan Pratt, Atari Corp. reflect those of Atari Corp. or anyone else. ...ames!atari!apratt
dbrooks@osf.org (David Brooks) (01/04/91)
In article <2792@atari.UUCP>, apratt@atari.UUCP (Allan Pratt) writes: |> dbrooks@penge.osf.org (David Brooks) writes: |> >...the keys in the top row, between "1" and |> >"=", get 0x76 arbitrarily added to their scancodes before being |> >returned to me. |> |> That's not arbitrary; it's part of the VDI spec, which is really just a |> codification of the behavior of the IBM PC keyboard/scancode |> characteristics. I don't know WHY it is, but the keys from 1 to = are |> defined to return scan codes 0x78 to 0x83, and that's just the way it |> is. Thanks for the explanation, Allan. A clarification: in the part you edited out I explained that this only happens when ALT is depressed. Otherwise, the scancodes 0x02 to 0x12 are returned. Is *this* also true of the IBM keyboard? -- David Brooks dbrooks@osf.org Systems Engineering, OSF uunet!osf.org!dbrooks