sritacco@hpdml93.HP.COM (Steve Ritacco) (11/16/89)
I picked up the technical description of the DECStation 3100 off the DEC public FTP server, and after reading it I have a few questions. Are the frame buffer boards in the monochrome and color systems the same except for the memory chips. The description of the PCC (programable cursor chip) mentions that on a monochrome system that the cursor may have gray levels. Does this mean that the DECStation is capable of gray-scale operation? I guess DEC doesn't sell it that way, but what happens if you connect a DEC monochrome monitor to a color system? Do you get 256 gray levels?
rwood@vajra.dec.com (Richard Wood) (11/18/89)
In article <15500001@hpdml93.HP.COM>, sritacco@hpdml93.HP.COM (Steve Ritacco) writes: > I picked up the technical description of the DECStation 3100 off > the DEC public FTP server, and after reading it I have a few questions. > Are the frame buffer boards in the monochrome and color systems the > same except for the memory chips. The description of the PCC (programable > cursor chip) mentions that on a monochrome system that the cursor may have > gray levels. Does this mean that the DECStation is capable of gray-scale > operation? I guess DEC doesn't sell it that way, but what happens if you > connect a DEC monochrome monitor to a color system? Do you get 256 gray > levels? The two SIMMS are different. The color simm uses 256K x 4 VRAMS, Mono uses 64K x 4. The drivers are different. The etch is different. The concept and impelementation are covered and fully disclosed in DIGITAL patent #xxxxxxxx (An easily upgradable video system). The PCC conects to the Video DAC and can be programmed with up to 16 grey/color levels. This is not exposed through X windows. You can connect a mono monitor to a color system. Green goes to mono. 50 ohm terminators must be installed on the Red and Blue BNC's. All 256 levels will be displayable. -- --------------------------------------------------------------------- Richard Wood Corporate Worksystems Team Digital Equipment Corp. ========================================================================
jg@athabasca.crl.dec.com (Jim Gettys) (11/22/89)
The frame buffer boards for mono and color are different; one is 8 bits/pixel, and the other is one bit/pixel; the addressing is different. It is more than just additional VRAM. You are welcome to connect a mono monitor to a "color" pmax, and get a grey-scale machine. If you order off the menu, rather than one of the stock configurations, you can configure a machine this way. It may take a bit longer to be shipped, as the standard configurations are set up for immediate shipment (which is why they are "stock" configurations); manufacturing doesn't have to think about the order to ship it... Jim Gettys Digital Equipment Corporation Cambridge Research Laboratory
wyatt@cfa.HARVARD.EDU (Bill Wyatt) (11/22/89)
From article <1302@crltrx.crl.dec.com>, by jg@athabasca.crl.dec.com (Jim Gettys):
< [...]
< You are welcome to connect a mono monitor to a "color" pmax, and get a
< grey-scale machine.
< [...]
Remember to two 75-ohm terminators to connect to the unused red and
blue video lines; you'll likely have ghosts otherwise.
Bill Wyatt, Smithsonian Astrophysical Observatory (Cambridge, MA, USA)
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