stefan@wheaton.UUCP (Stefan Brandle ) (07/04/90)
Our new Zenith LP's seem to have developed an antipathy for our ARCnet cards.
This only applies to the very recent (last month or so) arrivals -- previous
ones seem quite happy.
Anybody have any ideas? New _IMPROVED_ ROMs perhaps?
-Stefan Brandle
--
---------------------------------------------- MA Bell: (708) 260-4110 ---------
Stefan Brandle UUCP: ...!{obdient,uunet!tellab5}!wheaton!stefan
Wheaton College or stefan@wheaton.UUCP
Wheaton, IL 60187 "But I never claimed to be sane!"easton@zds-oem.UUCP (Jeff Easton) (07/05/90)
In article <2098@wheaton.UUCP>, stefan@wheaton.UUCP (Stefan Brandle ) writes: > Our new Zenith LP's seem to have developed an antipathy for our ARCnet cards. > This only applies to the very recent (last month or so) arrivals -- previous > ones seem quite happy. > > Anybody have any ideas? New _IMPROVED_ ROMs perhaps? I knew this question would come up sooner or later... Some of the ZDS computers are now shipping with a new VGA card that uses the Chips and Technologies 82C451 VGA chip. One of the special registers in this chip conflicts with the default I/O address for most Arcnet network cards, address $2E0. The reason for this is that the C&T chip uses all 16 bits of the IO address for decoding it's special register. The Arcnet card (and most other cards) uses only the first 10 bits, which happen to match the first 10 bits of the C&T chip's register. The problem shows itself as a "works most of the time" type. Usually the C&T VGA chip and Arcnet card will coexsist until some software tries to switch video modes. Then its lockup time. The solution is to reset the I/O address of the Arcnet card somewhere else and build a new IPX driver for this new address. Since we run Arcnet all over the place here at ZDS I've seen this problem many times recently. For these machines we reset the Arcnet card to IO= $2F0, Mem= $D000, IRQ= 5 and the problem goes away. I hope this info helps. > > -Stefan Brandle Jeff Easton Zenith Data Systems Systems Engineer OEM Engineering easton@andrews.edu -- or -- easton@zds-oem.zds.com Ottermania - It's spreading... I'd rather be Water Skiing....