pashler@sdics.ucsd.EDU (Hal Pashler) (05/04/87)
I just got some IBM PC's equipped with NEC GB1 display cards and NEC MultiSync Monitors. For various reasons, I need to read the memory location or port that will tell me whether the monitor is in vertical retrace or not. On my other PC equipment (Princeton Graphics SR-12 monitors + Sigma Designs Color-400 boards), I simply look at a particular port [$2da], and it with 16, and that value is 0 or 16 depending upon whether the monitor is in retrace mode. (I do this in turbo pascal, simply by calling Port[$2da]). Not surprisingly, this doesn't work on my new NEC equipment! And I haven't been able to figure out from the NEC documentation what I should do. Ideally, I would like to be able to simply look at a port, just as I do with the SR-12/Color-400 setups. I.e., if it can be done directly in Turbo Pascal without BIOS calls or what not, that will be much easier. Does anyone know what I should do? [If it isn't already obvious, only simple-minded concrete answers will be understood!]. Thanks you! Hal Pashler UC San Diego [pashler@nprdc]
wtm@neoucom.UUCP (05/06/87)
I don't have the tek specks to answer the question about which port to read to find out when you're in the vertical retrace time slot, but I do know that the GB-1 *IS* an Eva-480. Well, almost. I helped a freind write an article for Info World about the GB-1. We called NEC repeatedly, but got just about zero assistance. They can tell you how to plug it into the buss slot, and that's about it. They referred us grudgingly to Tseng Labs, when we pressured them about the fact we knew it appeared to be the same as the Eva 480. We were having trouble with the BIOS ROM on the NEC board. We couldn't get the Dr. Halo packaged with the GB-1 to work. Also we couldn't get Microsoft Windows to work. Interestingly, an *older* dated BIOS chip on an Eva 480 that we have did cause the GB-1 to fruction correctly in EGA and extended EGA modes. Tseng happily provided us with a new ROM for the GB-1. (Wow, talk about service!) The new ROM provided by Tseng also worked. We never did get any sort of hard information about the buggy BIOS from NEC. NEC also until very recently would not admit to the real (or is it accidental) fact that the Multisync can work at 70+ Hz scan rates. I don't trust NEC. As a final note, the Hercules emulation mode for the GB-1 and Eva must be rather limited, as we could get neither to work in Herc mode with Turbo Reflex (which is the only Herc mode program that we had on hand to experiment with). Presumably, Reflex does work properly with a genuine Herc board. To sum up, if you've done everything else and you're sure your doing things correctly, call Tseng to get a different BIOS chip. Sorry, I don't have the phone #s handy. Bill Mayhew Division of Basic Medical Sciences Northeastern Ohio Universities' College of Medicine Rootstown, OH 44272 USA phone:216-325-2511 (wtm@neoucom.UUCP ...!cbatt!neoucom!wtm)