dpbst3@unix.cis.pitt.edu (David P Brennan) (05/26/91)
I've been going through some programs that can be run in two modes: EGA and Hercules mono. My laptop has CGA. Now I know enough to know that *forward* compatability (i.e.: CGA to EGA) is entirely hardware-dependent, is *backward* compatability? Is it possible to force the CGA driver to emulate monochrome graphics? What I'm trying to avoid, of course, is the extra expense and simple bs involved in getting an expansion chassis, EGA or VGA card and monitor simply to run programs that *should* be able to run in mono. Any thoughts on this? Dave Brennan UPitt SLIS dpbst3@unix.cis.pitt.edu
dan@rna.UUCP (Dan Ts'o) (05/27/91)
In article <132214@unix.cis.pitt.edu> dpbst3@unix.cis.pitt.edu (David P Brennan) writes: >I've been going through some programs that can be run in two modes: EGA and >Hercules mono. My laptop has CGA. Now I know enough to know that *forward* >compatability (i.e.: CGA to EGA) is entirely hardware-dependent, is >*backward* compatability? Is it possible to force the CGA driver to emulate >monochrome graphics? What I'm trying to avoid, of course, is the extra >expense and simple bs involved in getting an expansion chassis, EGA or VGA >card and monitor simply to run programs that *should* be able to run in mono. If what you're asking is: Can I get a CGA laptop to run Hercules mono graphics programs ? The answer is no. The Hercules mono graphics mode is entirely different than CGA (and EGA and VGA, for that matter). Even EGA and VGA cards cannot run Hercules programs, although both can run CGA programs. Hercules graphics is a non-IBM "standard". But the CGA standard does have a mono graphics mode, at 640x200, which many programs, such as Windows, understands. Some laptops like Toshiba's support AT&T 6300 dual-CGA mode, yielding mono graphics at 640x400, which is more pixels than EGA. Windows understands this mode. Cheers, Dan Ts'o 212-570-7671 Dept. Neurobiology dan@rna.rockefeller.edu Rockefeller Univ. ...phri!rna!dan 1230 York Ave. tso@rockvax.bitnet NY, NY 10021