On 12/11/2020 7:57 AM, Bret Johnson wrote:
And none of this even addresses what happens if you try to print
something to a printer since a printer "Code Page" doesn't necessarily
match what's on the screen. As long as you limit yourself to the
first 128 ASCII codes you usually don't have probl
Hello Bret (and the rest):
On Fri, 11 Dec 2020 at 17:00, Bret Johnson wrote:
> The interaction between the screen (Code Page) and Keyboard is pretty
> critical so that everything is displayed correctly. In addition to
> DISPLAY, DOS has other "utilities" like "CHCP", "MODE CON CODEPAGE
> PREPA
>> * KEYB does not hook int 2Fh just for installation check. KEYB is
>> "codepage aware", as it has produce the appropriate character code
>> for that particular codepage (font), and that is why INT 2Fh/AD81h
>> exists: DISPLAY will call KEYB whenever there's a codepage change
>> request, so that
No problem!
The original note that Matthias Paul wrote a long time ago was very
interesting, but a very long post too :)
On Wed, 9 Dec 2020 at 20:43, tom ehlert wrote:
> > * KEYB does not hook int 2Fh just for installation check. KEYB is
> > "codepage aware", as it has produce the appropriate
> * KEYB does not hook int 2Fh just for installation check. KEYB is
> "codepage aware", as it has produce the appropriate character code
> for that particular codepage (font), and that is why INT 2Fh/AD81h
> exists: DISPLAY will call KEYB whenever there's a codepage change
> request, so that KEYB k
In addition to what Tom said (and regarding KEYB):
* int 09 calls int 15h/4Fh is guaranteed for PC/ATs. For older keyboards
where it does not happen, /9 option will hook the int9h handler to
precisely add this call to the present int9h handler.
* KEYB does not hook int 2Fh just for installation
> After installing new layout and calling int 15h/4Fh manually,
> causes correct scan code / ascii code pair is enqueued into the
> keyboard buffer and carry flag isn't set because something is
> changed this time. In short, this function is responsible for
> changing keyboard layout, obviously.
Hi everybody,
I would like to know what things are happening in the background when I change
keyboard layout in FreeDOS.
Normally, each time I press a key int 09 is called as a consequence of irq 1
and int 09 calls int 15h/4Fh, which has no effect when no layout is installed.
So, if it is ca
