CGA

                                by
                          Stephen Jones


CGA is a memory-resident program that allows you to run many graphics 
programs designed for CGA systems on your Hercules-compatible monitor 
and card.  It works with any software that uses standard DOS and BIOS 
calls to the graphics card.  Programs that write directly to the 
screen may not run under CGA.


USING CGA

Start the emulator by giving the command, CGA <Enter>.  CGA.COM 
must be in the root directory of the current disk, or in a directory 
on your hard disk that is included in the PATH statement in your
AUTOEXEC.BAT file.

You can also start the program with command-line switches.  Here's a 
rundown of those switches:

CGA M <Enter>

This switch starts the program in the monochrome mode.  Use this switch 
after you've finished running your graphics program.  CGA will return 
to the normal monochrome screen.

CGA $ <Enter>

In many cases, running CGA without a command-line switch will show you 
a screen that is too small.  Using the $ switch, you can expand the 
screen area.  In most cases, you'll want to use this switch.  Some 
software, however, will run better without it.  Experiment.

CGA B <Enter>

Some games bypass DOS completely, taking over the whole computer. This 
switch is for use with those self-booting programs.  To use this feature, 
give the command, CGA B <Enter>.  The CGA program will load, then you'll 
see a message asking you to insert your self-booting game disk and press 
a key.  The program will run as if you had a CGA card.

In a few cases, you'll need to tell CGA exactly where to install itself 
in memory.  This is a highly technical procedure, requiring you to know 
where the game program locates itself in your computer's memory.  If you 
can determine this, you can use this format:

CGA Bnnnn <Enter>

Replace the "nnnn" part of the command with the segment address where you 
want to load CGA.

You can combine command line switches, as well.  They must be in this 
order, however:

CGA B M $

You might, for example, want to use the "B" switch for a self-booting 
program, along with the "$" switch for a larger screen image.  The 
command would be:

CGA B $ <Enter>

NOTE:  CGA does not work with all CGA programs.  If a program will not 
run under CGA, your computer will lock up.  No harm will be done, but 
you'll have to reboot your system with the <Ctrl>-<Alt>-<Del> key 
combination.

Users with EPSON Equity computers equipped with Hercules-compatible 
graphics cards may find that CGA will not work at all with their systems. 

CGA will not work with EGA cards that emulate Hercules graphics on a 
monochrome monitor. 
 
This software is in the public domain. You may make copies and give it 
away to friends. If you like CGA, feel free to send a donation to the 
author. The suggested donation is $5. If the program doesn't work on your 
computer, drop me a line! 

Stephen Jones 
4 Riverside Grove
Wainuiomata
New Zealand