kmcvay@oneb.UUCP (Ken McVay) (12/07/90)
Someone recently described their AT to me and asked if it would accept an upgrade to EGA. The system is a 5-year-old Compaq Portable 286, model 101710. I am told it has a built-in 9" mono display and composit jack for RGB output. I am unfamiliar with Compaq, and would like to find out if the machine will accept an EGA card, or if the RGB graphics are built into the motherboard, and can't be over-ridden... Anyone out there know? -- 1B Systems Management Limited, Nanaimo, British Columbia | kmcvay@oneb.uucp --------------------------------------------------------------------------- Canada's FrontDoor Automated Electronic Mailer Distributor - (604) 754-7423
marshall@wind55.seri.gov (Marshall L. Buhl) (12/11/90)
kmcvay@oneb.UUCP (Ken McVay) writes: >Someone recently described their AT to me and asked if it would accept >an upgrade to EGA. Not using the internal monitor. >The system is a 5-year-old Compaq Portable 286, model 101710. I am >told it has a built-in 9" mono display and composit jack for RGB output. That sounds correct. >I am unfamiliar with Compaq, and would like to find out if the machine >will accept an EGA card, or if the RGB graphics are built into the >motherboard, and can't be over-ridden... >Anyone out there know? I guess I do. I've done just that with the Portable 286. If you open it up, you will notice that the video comes from an add in card. It supports the Dual Mode monitor that is built in. The monitor normally runs in mono mode (no graphics), but you can manually enter "MODE CO80" and it will switch to CGA 2 color mode. I guess many software packages will switch mode for you. This allows you to do low resolution graphics. All in all, it's a rather poor picture, that's why it's called the Crummy Graphics Adaptor. I'm currently working with OSHA to have these things banned from offices across America. ;-) You can plug a CGA compatible RGB monitor into the nine-pin connector on the end of the board. My user complained of the poor picture, so I pulled out the video card and installed an EGA card. I just left the cable leading to the internal monitor hanging in there. It will no longer work. I then connected an EGA monitor to the external connector. This pretty much eliminates the PC from being a luggable (32 pounds not counting the external monitor!). You also need to change a jumper that is difficult to get to. It is located under the little cage that stores the power cord. I think it is the "ED" jumper. It is normally set to 2-3, but must be changed to 1-2. You'll need to pull out all the cards and use needle nose pliers (unless you have really tiny hands). I've recently done this to install a Herc compatible. It's been years since I've done it for EGA. The Technical Reference Manual Vol. I on page 2-76 says 2-3 is for "COMPAQ Graphics or RGB video controller" and 1-2 is for "Non-COMPAQ monochrome/text video controller," so maybe you should try it first without changing the jumper. I vaguely remember having to change it for EGA though. I'm just not sure. IMPORTANT WARNING: I had the ROMs changed in these old PCs because of problems with 80287 errors. This was after the EGA was invented, so there may be no support for EGA in the original BIOSes. The ROMs cost me $50 several years ago. If you can, try this without spending any money. I'm currently trying to upgrade the ROMs in some old Compaq 386/16s because they don't support 3.5" floppies and they want $75 for them. I don't know if they're charging more for ROMs now or just 386 ROMs. I'd hate for your friend to go out and spend a lot of money for EGA cards and monitors and find out you have to spend another $75 for new ROMs. I would guess, though, that your friend has the stuff lying around or else he would be talking VGA instead. I wouldn't invest any real money in an EGA at this late date. -- Marshall L. Buhl, Jr. EMAIL: marshall@seri.gov Senior Computer Missionary VOICE: (303)231-1014 Wind Research Branch 1617 Cole Blvd., Golden, CO 80401-3393 Solar Energy Research Institute Solar - safe energy for a healthy future
liberato@dri.com (Jimmy Liberato) (12/23/90)
In article <580@oneb.UUCP> kmcvay@oneb.UUCP (Ken McVay) writes: >The system is a 5-year-old Compaq Portable 286, model 101710. I am >told it has a built-in 9" mono display and composit jack for RGB output. > >I am unfamiliar with Compaq, and would like to find out if the machine >will accept an EGA card, or if the RGB graphics are built into the >motherboard, and can't be over-ridden... Further, does anyone know if those Compaq portable mono screens can be driven with a Hercules card (hence graphics capability). If so does any one have a pin-out of the screen connector so I could make an adapter for the Herc? Thanks! -- Jimmy Liberato liberato@dri.com ...uunet!drivax!liberato