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More than 640K in an IBM PC

On that CGA system, installing a Hercules monochrome graphics card and using UMBHERC.SYS from PC DOS 6.1 or higher would give you 60K of UMB space for loading drivers and TSRs -- and you'd still be able to use the Hercules card in MDA text mode on a monochrome display. Or at least that's how it's supposed to work; it's been years since I had a Hercules-compatible card.

I was under the impression that Hercules cards have 32K, which means I would gain 28K.
 
Without checkng it I have a Phillips which when booting reports more than 640kmemory.
It was a bit disconcerting when it frst did the POST and just kept going after 640k
It otherwise responds normally to the MSDOS OS. Just checked a label and the suspect machine is a Phillps model 3105. Didn't start it up to see the ram, but I believe it was this box. There was some discussion on this machine years ago on classiccmp.

Lawrence
 
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From http://everything2.com/e2node/Hercules%20Monochrome%20Graphics%20Adapter :

"The HGC sported 64k of RAM, enough to support 8 pages in text mode, or 2 in graphics mode. This memory was mapped to B0000h-BFFFFh in the main processor's address space, with B8000h-BFFFFh able to be turned off to allow simultaneous use of the HGC and a color video card."

Wasn't there an utility named "HALF.COM" and "FULL.COM" that activated the graphics pages? I really don't have the Hercules software, so I don't know how to use them.

BTW, If anybody got the Hercules software disk, I would be interested in a copy of the files/raw-image of the disk.
 
I believe the Hercules starts in half mode, then you have to program the registers to set it to full mode. I was able to get one working in a dual monitor configuration with a CGA card without obvious difficulty. I didn't fully test it, however.
 
Wasn't there an utility named "HALF.COM" and "FULL.COM" that activated the graphics pages? I really don't have the Hercules software, so I don't know how to use them.

BTW, If anybody got the Hercules software disk, I would be interested in a copy of the files/raw-image of the disk.

Which ones? I've got the disks for my Graphics Plus cards (a very cool variation on the basic design that allowed for 12-bit characters and downloadable fonts).
 
Which ones? I've got the disks for my Graphics Plus cards (a very cool variation on the basic design that allowed for 12-bit characters and downloadable fonts).

If it is for the GB-112, I'll strongly like a copy since I actually bougth one of therse cards not long time ago.
 
I believe the Hercules starts in half mode, then you have to program the registers to set it to full mode. I was able to get one working in a dual monitor configuration with a CGA card without obvious difficulty. I didn't fully test it, however.

Some software insists on using B800 in Hercules mode, and as a result can't be used in a dual-display system (the color monitor fills up with garbage). I know that Sierra games and Lotus 123 do this.
 
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