🚀 go-pugleaf

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....