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- Number: F2TH072590U200
- Subject: Asynch Bridges in 386 Fast Machines
- Date: August 2, 1990
- OS Version: 2.1x
- Revision: 2.12, 2.15C
- Shell Version: N/A
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-
- GENERAL
- INFORMATION: This problem arose on NetWare v2.15 Rev C, but we reproduced
- it and made the fix on v2.12.
-
- PROBLEM: Using a v2.15C bridge with WNIM card and Hayes modem, the
- bridge initialized LAN A (in this case an NE1000), but hung
- after the "Initializing LAN B" message. The EGA screen
- blanked after a couple of minutes. A scope on the line
- showed the ATZ message being correctly sent to the modem
- (a Hayes 2400), and the OK response being sent back.
-
- The weird thing was that a Hayes Quad modem, configured as
- a 2400, worked fine some of the time.
-
- SOLUTION: The machines being used by the customer were various Compaq
- and other quality 386 machines; ours machines were AST 386s.
-
- When we slowed down the machine to "slow as a snail" mode,
- it all worked.
-
- When we used a COM port, we saw about an 80% success rate.
- We didn't test slowing down the machine with a COM port.
-
- COMMENTS: The bridge waits for the OK response from the modem after
- resetting it with the ATZ command. On a fast machine, we
- suspect that the bridge times out before the Hayes 2400
- sends the OK response. A faster modem (in terms of command
- response) beats the timeout.
-
- (X) This information was verified in the lab.
-