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Olivetti M24/AT&T 6300/Xerox 6060 Display Enhancement Board (DEB) materials available

Trixter

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Olivetti M24/AT&T 6300/Xerox 6060 Display Enhancement Board (DEB) materials available

While I haven't tested the hardware yet, I've archived the software and manuals for the DEB:

ftp://ftp.oldskool.org/pub/drivers/ATT/Display Enhancement Board (DEB)/

What's the DEB?

The DEB is a rare upgrade board for the M24's Video Display Controller (VDC). The VDC is capable of CGA emulation as well as a 640x400x2 mode, and the ability to have two 320x200x4 CGA graphics pages. The DEB sits in one of the two 16-bit slots on the M24 motherboard and connects to the VDC via a ribbon cable, and adds three more 640x400 bitplanes. These can be combined with the VDC's bitplane into 4 total bitplanes, giving 16 colors in 640x400. The DEB can also operate in only 3 bitplanes, and let the VDC do whatever it wants, then combine the result. The can be used to create a 640x400x8-color graphics screen with, for example, quickly updating scrolling text or supplemental graphics coming from the VDC.

The DEB also has a hardware lookup table to translate RAM values into pixel colors, and it can cycle through colors in a "dithering" effect that allows you to create additional colors via temporal dithering (ie. alternating between 2, 3, or 4 colors every display cycle). While cycling through 2-color combinations can be interesting on a color monitor (136 unique combinations, about 40 of which would not flicker distractingly), hooking up a monochrome monitor is potentially much more interesting: The colors are translated to 16 shades of gray, and the monitor itself has somewhat slow phosphors. Because the display is analog, has slow phosphors, and harsh flickering would not be perceivable, this means up to 4 color combinations could be used, increasing the number of available grayscale levels from 16 to 3876. (With bit-banging it might be possible to switch palettes every scanline, allowing more than 16 onscreen at once, but this is unverified.) The LUT is also capable of cycling through colors spatially (it has a counter that updates on every new pixel), but the usefulness of this is not yet obvious to me. It can also "blink" pixels between colors, like when you set the blink attribute in text mode -- the usefulness of that is dubious at best.

Additionally, since the DEB is a separate board with its own display output, it is possible to connect both a monochrome and a color monitor to the system at the same time (although they share the same memory space so the applications for this is limited.)
 

MissArgent

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I've always wanted to see the DEB in action! If memory serves, Windows 2.11 and onwards have drivers specifically for it. Was there anything else that made use of it out of the box?
 

Valerio

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This is great - thanks for posting this! I never realised the DEB was closer to a replacement video card - somehow I thought it was a simple daughterboard or something like that!

Also from a quick scan of the documentation it seems you can actually have two monitors connected at the same time - now seeing that in action would be awesome!
 

Trixter

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I've always wanted to see the DEB in action! If memory serves, Windows 2.11 and onwards have drivers specifically for it. Was there anything else that made use of it out of the box?

Out of the box, I think CSHOW had a DEB driver, but I'd never heard of anything supporting it until John mentioned GEM had a driver for it (!)

Also from a quick scan of the documentation it seems you can actually have two monitors connected at the same time - now seeing that in action would be awesome!

Well, read further: One monitor shows the VDC and the other shows the DEB. That means both monitors will display VDC memory, and the other monitor will display DEB memory -- so it's not really the same thing as two-monitor support in DOS like we have come to expect from CGA+MDA.

Someday I'll hook it up and provide a demonstration -- thankfully the package comes with example GWBASIC programs, so I won't have to try to decipher the LUT instructions (which appear more complicated than they need to be).
 

normanator

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normanator

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Thanks, bud! Mine's been in a box for ~18 years, and I never have tried it. Actively working on resuscitating my PC6300 system, and then plan to install this finally. Looks like you got the full package. Nice! Mine is everything you've got minus the disks and the PAL chip. Thankfully my main VDC is the 318 type and doesn't need the PAL chip upgrade to support the DEB. (Per the manual, only the 317 VDC needs the PAL.) Mine did come with the outer slip cover around the white box. Quite beat up, but these things are unicorns as it is. Feel free to add it to your picture archive. If you need a better shot, let me know.

IMG_2623.JPG

Will post some updates when I get it running.
 

Trixter

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Appreciate the use of the picture; snagged (and will attribute you as the source). If you can make a higher-res version of the box, both sides, that would be great. Someday I hope to do a video on the DEB. I definitely lack the slipcover.
 

Trixter

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this card is the same as the STB Super Res 400, no? Show photos. I know there are some posted already somewhere.

No, it's definitely a proprietary card created by Olivetti to add additional planes to the existing VDC. This adds 640x400 16-color support, as well as "136-color" support (the DAC can flash between two colors in hardware), and the ability to overlay a textmode page on top of graphics mode and have them be addressed independently. The main disadvantage is that hardly anything supports it.

There are pics of the actual board at oldskool.org

I run oldskool.org ;-)
 

1ST1

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The naming for that card is quite confusing, if you have a look on that capa.pdf, you can see that it would fit in M24 (and M21 but does not make sense here), M28, M240 and M280.

Additionally you also find the name "Video Enhancement Adapter" (VEA) for the GO329 in some technical documents for M24. So real Olivettians don't talk about "DEB" or "EGC" or "VEA", but about "GO329", this is more precise.

But as the GO329 has M21/M24 proprietary 16 Bit connector, it can not fit in M240, as it only has standard 8 Bit ISA like any other XT as well, and it can not fit into M28 and M280 as they are 80286 AT with standard 16 Bit ISA slot. If you have a look into cap2.pdf (M240), and cap4.pdf (M280) you also will not find any mention of the GO329 what is the trueth, as it does not make sense because of the slots. But you still find it in the cap3.pdf (M28), but there also it does not make sense.

But M240, M28 and M280 can support the 640x400x16 modes, without using the GO329 if they have the original OEC/OVC (EGA/VGA) cards. There are also monochrome/greyscale cards (OGC,PGC) which only support the 640x400 in monochrome, like M24 OGC card.
 

pevalcas

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Stefan, the OEC/OVC doesn't support by default the 640x400x16 DEB mode. Unless you have a special BIOS routine of driver. I don't think the Paradise chip equipping the OEC or OVC supports the DEB mode and the Look Up Table that was specific to the DEB.

The 640x400x16 on 4 planes, with the specific dithering, blinking, special effects, double 8 colors text on graphics mode, was specific to the DEB hardware.

If anybody among you needs additional clarifications,I'm ready to help!

The PEGA1, PEGA2 and PEGA2A chips and the PVGA1A and PVGA2A (or WD90C00) only supported the standard 640x400x2 colors mode (0x40). The DEB used 3DDh register, 3DFh register that are not implemented in the Paradise/WD chips.

Regards, Vincenzo.
 

Trixter

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To further clarify: They don't actually support the 640x400x2 mode, but instead pass the BIOS calls to the host BIOS. So if you use those cards in a non-M24 system, you won't get 640x400x2 support.
 

tonata

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The FTP link does not work. How does it look like this DEB?
I have an Olivetti M24 with color monitor, but this is not with DEB I suppose?
 

1ST1

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deb.jpg - Click image for larger version  Name:	deb.jpg Views:	0 Size:	118.7 KB ID:	1210780

YESSSSSSS !!! Tschaka!

Do you know how to replace the graphics driver in Windows 1.0x? I don't want to reinstall, just swap the video driver to enhance from 640x400 1 to 16 colors...

For GEM it's quite easy, I only need to replace a driver file, https://web.archive.org/web/20200224...ers/video.html

This is my GEM.BAT in c:\DOS for my FreeGEM-Installation

Code:
...
:STEP1
ECHO Graphics Driver?
ECHO o - OGC 640x400x1
ECHO c - CGA 640x200x1
ASK3 "-> " oc
IF ERRORLEVEL 2 GOTO CGA
IF ERRORLEVEL 1 GOTO OGC
:CGA
COPY C:\GEMAPPS\VIDEODRV\SDCGA8.CGA C:\GEMAPPS\GEMSYS\SDPSC10.VGA
GOTO :STEP2
:OGC
COPY C:\GEMAPPS\VIDEODRV\SDATT9.EGA C:\GEMAPPS\GEMSYS\SDPSC10.VGA
GOTO :STEP2
:STEP2
...
(in STEP2 it will ask to load ACC or not and hide *.acc or not, to save memory or to load full comfort, and then in step 3 it will ask to enable GEM 1.20 or GEM/3 desktop app)

I just have to enhance this by adding to copy SDDEB8.EGA
 
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