Ref: 13930005
Title: Upgrading a CS to a GS/X.25-IP or GS/X.25-XNS
Date: 4/20/90

Copyright 3Com Corporation, 1991.  All rights reserved.

To upgrade from a CS to a GS/X.25-XNS or GS/X.25-IP, follow these steps:

1.  Replace the MCPU with an MCPU-20.

2.  Replace the 48TPI disk drive with a 96TPI drive.

3.  Replace the EC/1 with a 512 KB EC/2.  If an EC/2 is already installed,
make sure that it is 512 KB (replace it if needed with a 512 KB EC/2).
Upgrade all EPROMs with the current rev.

4a. For an XNS gateway, replace software with the current release,
SW/20-XNS-X.25 Release 1.0 (83-0186-00).

4b. For an IP gateway, replace software with the current release,
SW/20-IP-X.25 Release 2.0 (83-0147-01).

3Com recommends that you make sure all boards have the current hardware
revisions.  If they do not have current revisions, send them in for
upgrade.  For example, a 512 KB EC/2 (06-0021-03) at rev. 03 should be
upgraded to rev. 04.

You may find that your CS is old enough that the SIO board part
numbers do not reflect their current configuration, making it difficult
to determine their actual rev level.  For example, if the SIO-V.35H
(06-0016-03) has M1SYNC (rather than M0HDLC) EPROMs, it is actually an
SIO-V.35S (06-0016-13), though the board itself is labeled a 06-0016-03.
If the SIOs do need to be upgraded, upgrading the CS may not be any less
expensive than buying a GS.  (However, if you only need to obtain an
MCPU-20, a 96TPI disk drive, and a 512 KB EC/2, you can save money by
upgrading rather than by replacing the unit.)
