Re: A2Programmer needs help ... ProDOS MLI calls

[dempson@actrix.gen.nz (David Empson)]

Rubywand <rubywand@swbell.net> wrote:

> Cturley2 writes ...
> > 
> > FROM: a2programmer
> > 
> > I need to know the assembly commands to initiate a PR#3 command from
> > within PRODOS.
> 
>      One way to do a PR#3 is to JSR C300 ...
> 
> 20 00 C3
> 60

It is a good idea to ensure you have a neutral character in the
accumulator before calling C300.  If the accumulator happens to contain
a control character, you may get strange effects.

(I forgot this in my own example.)

>      A way to go back to 40 columns is to send the key commands (Esc
> Control-Q) ...
> 
> A9 2B
> 20 ED FD
> A9 11
> 20 ED FD
> 60

This does not work.  The ESC Ctrl-Q sequence is handled by the keyboard
input routines, not the character output routines.  You need to output a
Ctrl-U character (21, or $15) to switch off the 80-column firmware.