Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!lll-crg!rutgers!sri-unix!hplabs!hao!gaia!zhahai
From: zhahai@gaia.UUCP (Zhahai Stewart)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Using the EGA card and a monochrome monitor
Message-ID: <130@gaia.UUCP>
Date: Tue, 11-Nov-86 19:52:53 EST
Article-I.D.: gaia.130
Posted: Tue Nov 11 19:52:53 1986
Date-Received: Wed, 12-Nov-86 20:23:50 EST
References: <279@rocky2.UUCP>
Distribution: net
Organization: Gaia Corp, Boulder, CO
Lines: 31
Summary: EGA mono feasible but not well supported

In article <279@rocky2.UUCP>, reintom@rocky2.UUCP (Tom Reingold) writes:
> Does anyone know how, if at all, I can do graphics in monochrome
> with an EGA card? 
Yes, the EGA will support graphics on a TTL monochrome monitor, such as the
IBM Monochrome Display, the Amdek 310A, Princeton MAX 12, etc.  The new
BIOS extension on board the EGA supports 640x350x3 brightness levels as
video mode F (hex).

Unfortunately, before the EGA came out, Hercules had already established
a defacto monochrome graphics "standard", emulated by many other vendors.
This provides 720x348x2 levels, and is totally incompatible with the EGA
in address, bit mapping, etc.  This "standard" is much more widely supported
than IBM EGA monochrome.  So if you have or are considering a package with
"monochrome graphics" features, be very careful to check that it supports
EGA monochrome mode.

Also, some packages (applications or graphics libraries) may support the
EGA, but only in color modes (color is pretty popular nowadays, since the
EGA provides similar resolution in color or monochrome).  Check.

Last warning: Some people connect a CGA (color Graphics Adapter) or clone
to a single color monitor, usually via composite video (RCA plug rather
than DB-9 connector) [ Exception for Princeton Graphics MAX-12E which can
connect with CGA in TTL/DB-9 mode monochrome. ].  This allows 640x200x2
graphics (or 320x200), but is totally incompatible with either of the
above monochrome modes (EGA or Hercules).  This appears to be color graphics
to the software level.  This is seldom done with the EGA, since it does not
have composite video outputs (besides, why use an EGA with a low resolution
monitor - waste of money).

Hope this helps.           zhahai   /   HiSystems