Ref: 11630017
Title: MultiConnect Controller and Module Revs (as of January 1991)
Date:  1/23/91

Copyright 3Com Corporation, 1991.  All rights reserved.

MULTICONNECT CONTROLLER
     3787-01 rev A -- Original fab assembly when MultiConnect was
                      introduced.
     3787-02 rev B
             rev C -- Improved four repeater performance.
             rev D -- Improved four repeater operation with TP.
             rev E -- Allowed for correction of jitter budget with
                      150-ohm Type 1 wire.
             rev F -- Changed the stake pin because the holes
                      were too large and the pins would fall out
                      before wavesolder.
             rev G -- Changed the stake pin back to the original
                      part number.
                      Reason:  the fab was changed to make the
                      stake pin holes smaller.
             rev G1-- Changed propagation delay in data recovery
                      circuit.  Added more delay to clock (40% fallout).
             rev G2-- Corrected documentation.


PAIRTAMER MODULE
     6229-00 rev B -- Obsoleted:  not compliant with FCC Class B.
     6229-01 rev C1


TWISTED PAIR MODULE
     6756-00 rev E


THIN ETHERNET MODULE (BNC)
     3796-01 rev 11 -- Pre-production units.
     3796-02 rev A  -- Never shipped.
     3796-03 rev A  -- State diagram corrected to match 802.3 spec;
                       reconnect logic corrected; corrected fragment
                       extension algorithm.
             rev B  -- Improved performance in high traffic situations.
                       Changed in partition specification.
     3796-04 rev A  -- Incorporated jumper wires into fab.
             rev B  -- Changed from partition on 32 collisions to 64
                       collisions.
             rev C  -- Changed minimum differential output voltage
                       specification to improve mfg yield.
             rev D  -- Changed BNC connector; removed GAL socket.
             rev E  -- Changed partition switch to sealed type.
             rev F  -- Changed GAL equation to prevent partitioning on
                       transmit of long packet.
             rev G  -- Added a socket for the GAL at U12.  GAL was
                       being damaged when being replaced.  No effect
                       on field units.
             rev H  -- Changed capacitor, C16, from 100 pf, 5%, 50V
                       to 150pf, 5%, 50V.  Excessive noise, causing
                       approximately 10% fallout in test.
             rev I  -- Created new serial number barcode label.  No
                       effect on field units.
             rev J  -- Changed the position of a jumper installed at
                       the assembly vendor in order to verify the
                       stake pin installation.  No effect on field units.
             rev K  -- Not pertaining to any rework.


TRANSCEIVER INTERFACE MODULE (DIX)
     3793-01 rev 11 -- Pre-production early run of modules.
     3793-01 rev A  -- Rolled product into production.
     3793-02 rev A  -- Never shipped.
     3793-03 rev A  -- Corrected state diagrams; FIFO overruns;
                       XMT recovery time.
     3793-04 rev A  -- Incorporated jumper wires into fab; changed from
                       partition on 32 collisions to 64.
     3793-05 rev A  -- Corrected differential threshold level;
                       incorporated jumpers into fab.
             rev B  -- Corrected documentation.
             rev C  -- Met the minimum differential output voltage
                       specification.
             rev D  -- Changed partition switch to sealed type.
             rev E  -- Changed GAL equation to prevent partitioning
                       on transmit of long packet.
             rev F  -- Added a socket for the GAL at U10.  GAL was
                       being damaged when being replaced.  No effect
                       on field units.
             rev G  -- Created new serial number barcode label.  No
                       effect on field units.
     3793-06 rev A  -- Reprogrammed GAL for false partitioning.
             rev B  -- Updated documentation.

