VEXP - A Toshiba Tecra 710/20/30/40 Video Expansion Utility

Version 1.3
20/8/97

This utility provides the following features:-

* Toggles DOS graphics expansion on/off (play DOS games full screen !)
* Supports ledgable 25, 43 & 50 line DOS text modes
* Provides a reverse video DOS text mode (black text on white background)

This is a utility to control the graphics/text expansion features built
into the C&T 65550/4 graphics chip. Toshiba do not provide their own
utility with the machine, so I thought I'd better write one.

Usage:

VEXP M0  { turns off graphics expansion, uses font stretching (Toshiba default)}
VEXP M1  { turns on graphics expansion, no font stretching }
VEXP M2  { turns on graphics expansion with font stretching }

VEXP 25  { 25 line text mode }
VEXP 43  { 43 line text mode }
VEXP 50  { 50 line text mode }

VEXP T   { load TSR to enforce mode changes }

VEXP U   { unload TSR }

VEXP R0  { white text on black background (default) }
VEXP R1  { black text on white background }

VEXP ?   { Help screen }

The modes can be used together, e.g.:-

VEXP M1 43


Installation:-
-------------
1) Copy the VEXP.COM program into a directory on your path (eg C:\WINDOWS)
2) Delete the old version of VEXP (VEXP.EXE) if it is installed
3) That's it !


Suggestions:-
------------

Place VEXP M2 T in your AUTOEXEC.BAT file to enable graphics/font expansion 
permanently

To change text modes use commands like

VEXP 50
VEXP 25

at the DOS prompt. Or set your window size in the Win'95 PIF file.


This program may work with other notebook computers using the C&T 65550/4
chipset. If you have success using it with another type of notebook, please
mail me.


Revision history
----------------

Ver 1.0  8/10/96 (First release)

Bugs:-

Using VEXP M2 50 gives a nice 50 line mode, but unfortunately the font
stretching registers are rewritten when changing video modes (presumably
by the BIOS), this results in reverting to the horrible Toshiba 43/50 line
mode. There is nothing I can do about this, short of writing a TSR.
VEXP M1 43 does not suffer from this problem.


Ver 1.1  5/4/97

Changes:-

1) TSR option added to stop BIOS resetting graphics/font stretch when
   changing modes.
2) Re-written in TASM, now a .COM file
3) Hardware check for C&T chip removed
4) Reports status/help when used without parameters

Ver 1.2  6/4/97

1) Unload TSR option added
2) Less aggressive mode change enforcement used - stops screen
   'twitching' in some DOS programs

Known Bugs:-

1) 40 column mode does not work properly yet
2) Multiple Win'95 DOS windows of mixed sizes will confuse VEXP
3) Using Windows in 800x600 or 640x480 'stretched' modes confuses the mouse
   driver (it still thinks the screen is postage stamp size). If anybody
   knows how to fix this, please mail me.

Ver 1.3  20/8/97

1) Reverse video text mode added (R0,R1 options)
2) Highlight text mode added - but not working (H0,H1 options)


Legal stuff:-
-------------

I am not liable for any use (or misuse) of this program whatsoever. I am not
an employee of Toshiba, just a private individual.

Again - use this program at your own risk.

This program is freeware (But you can send money if you like !)


About the author:-
------------------

I am:-

Adrian Gradwell

mail: agrad@dil.u-net.com
web:  http://www.dil.u-net.com