EGA under Xenix

[Kai-Uwe Rommel]

Situation:

Programming advanced text modes and graphics on an EGA under DOS normally
goes one of this ways:

1. Using MS-Windows or GEM

2. Using a library like these of Turbo C/Pascal or MS-QuickC

3. manually

These ways all do the same:

- use BIOS calls for mode setting (Resolution, Colors, Font size ..)
- write directly to video RAM for displaying Information
  (characters, attributes/colors, pixels)
- program the hardware directly (palette registers ...)


My problem:

I want to use the EGA under Xenix not only in the simple 80x25 mode
because I have a hires EGA with a 100x42 text mode with 8x14 font !
The minimum requirement for me is to be able to use the 43 line mode.

1. How can I set up any text mode (generally) without BIOS calls but
   programming the hardware (especially 80x25 and 80x43 standard
   modes) ?

2. Is the Xenix console driver (SCO 286 Xenix 2.2.1) good enough to
   recognize the 43 lines and to use them properly ?
   (If not, what's to do ?)

To set up graphics mode 640x350x16, the stty program can be used.
But my EGA does 640x480, 800x600 and 1024x480 (all x16) too.

1. How can the graphics modes be set up by programming the hardware
   directly ? (at least I need info to set up 640x350 this way, the rest
   is my job, because I do not expect that many people use the same
   NEL EGA-1024)

2. Because in graphics modes a mouse is often useful, I am interested
   in info about the hardware protocol of the Microsoft serial mouse
   too, because there is no driver for Xenix and I have to communicate
   directly to it via /dev/tty2a. An alternative would be a bus mouse
   because this NEL EGA has a bus mouse interface on board for a
   Microsoft one. 

So. Thats all. If you work on the same problem(s) and know about
a solution, I would be happy to get mail from you !

Thanks, Kai Uwe Rommel