KRULWICH@C.CS.CMU.EDU (Bruce Krulwich) (09/04/86)
has anyone out there ever tried plugging an IBM EGA card into an AT&T 6300 pc?? aparantly there is some way to disable the normal graphics board and just use the EGA. (note: i am NOT talking about the AT&T DEB) bruce krulwich arpa: krulwich@c.cs.cmu.edu bitnet: bk0a%cmcctc@cmccvma uucp: ... !ucbvax!c.cs.cmu.edu!krulwich ( ?? )
lowe@psuvax1.UUCP (Tom Lowe) (09/08/86)
In article <3555@brl-smoke.ARPA> KRULWICH@C.CS.CMU.EDU (Bruce Krulwich) writes: > > >has anyone out there ever tried plugging an IBM EGA card into an >AT&T 6300 pc?? aparantly there is some way to disable the normal >graphics board and just use the EGA. (note: i am NOT talking about >the AT&T DEB) > > >bruce krulwich > >arpa: krulwich@c.cs.cmu.edu >bitnet: bk0a%cmcctc@cmccvma >uucp: ... !ucbvax!c.cs.cmu.edu!krulwich ( ?? ) The AT&T PC6300 computer is capable of using an EGA board only it it has ROM BIOS version 1.43. If your machine has 1.21 or less, an upgrade kit can be ordered for $35.00 and includes 2 replacement ROM chips and a replacement PAL chip. The part number is 105203780 and can be ordered from AT&T National Parts at 1-800-222-PART (7278) You also must disable your display controller board or replace it with what is called a Video Bridge Adapter which simply connects the Motherboard with the Bus Converter board. Part number 405067281. I don't know the exact price, but it can also be ordered from 1-800-222-PART. Some of the more recent PC6300's have a display controller that can be disabled by removing a 74LS00 chip located at position 6H directly above the black power lead and then connecting the following pins in the socket: 6 and 7....and with another wire: 3,8,11,and 14. If this chip is soldered to the board, then you must use the Video Bridge Adapter. NOTE: unsoldering the soldered chip on your display controller will void your warranty and you won't be able to return a board for repair/exchange credit should something go wrong! A new configuration of the PC6300 is starting to come out also... the CPU1Z. This is a single floppy drive system with the 1.43 ROMS BIOS and a video controller card that is disabled with a single jumper. There is a 3-pin jumper (W1) locatd between 1E and 1D (That's the left-hand ege, half way down from the top). When Pins 2 and 3 are strapped, the video board is normal, When Pins 1 and 2 are strapped, the video board is disabled. Owners of PC's under warranty and those with maintenance contracts may direct further questions to the AT&T PC Hotline at 1-800-922-0354. --Tom Lowe