AW: CGA card (Mitsubishi Electric) with 192K RAM?

[Fred Cisin]

On Mon, 7 Sep 2020, Jules Richardson via cctalk wrote:
> It's a shame that the hard disk in the machine is either snafu or has been 
> wiped - the contents would have helped shed light on things. There's an EPROM 
> as part of the video hardware; anyone know of a DOS-based util to poke at the 
> contents and/or snarf them into a file on disk? It's possible I suppose that 
> there might be some useful strings hidden away in there.

"DOS based utility program to poke at the contents and/or snarf the int a 
file on disk"?
DEBUG.COM
Present since PC-DOS/MS-DOS 1.0
STILL there.
As it got more bloated, it eventually became a .EXE file, but still 
FALSELY named .COM (DOS didn't care which of the two extensions, but 
looked for "MZ" in first two bytes of the header.)


The character generator ROM might not be accessible in the memory map.
OR, the ROM could be a BIOS extension.

There did exist some CGA-like boards with more RAM.  I had one (from 
Plantronics??) that was a double board, with 640 x 400, and 640 x 200 with 
more colors.  It was NOT the same as yours, in at least trivial ways - it 
did not have an RCA, but had composite on an RF modulator (4 pin) 
connector.

The Vogons page
https://www.vogons.org/viewtopic.php?t=57843
while very useful, is immediately suspect, by starting out with saying 
"100% compatible".  It was NOT.  Compatible enough for MOST stuff, but of 
course, it did not have the IBM BASIC ROMs, and therefore came with 
GW-BASIC.


My buddy had a few Sperry 5160-like machines, as well as some PBM-1000's 
(Micropro CP/M machine).  They were dumpstered immediately when he died 5 
years ago.


--
Grumpy Ol' Fred     		cisin at xenosoft.com