[comp.sys.novell] 3Com 503 incompatible with the DL2000

beecher@cunixf.cc.columbia.edu (Ben Beecher) (06/08/91)

I found out from Dave Scott at Dayna Communications that the 3Com 503
Ethernet board is not compatible with the DL2000 LocalTalk board.  The
3C503 uses pull up resistors on the interrupt pins, bringing the
voltage up to 5 volts when there are no interrupts.  The DL2000 uses
pull down resistors instead.  He explained that I can make it work by
polling the DL2000 instead of using the interrupt mechanism but this
will decrease the throughput of the board.  I tested it and it works.

I haven't seen this compatibility problem mentioned in the
documentation or in this newsgroup.  I am posting this message because
it could save someone a lot of time and frustration if they are using
these two boards in the same server.

** The 3C505 is compatible with the DL2000, however. **


Ben Beecher		beecher@cunixf.cc.columbia.edu
Network Planning	212-854-7439
Columbia University