Compaq Portable II User Manual

YY Bit location of the low byte (B = 0)
ZZ Bit location of the high byte (B =1)
For example, for the Version 1 system board, memory error message
"02000 10010" specifies chip U47.
Use Tables 5-14 through 5-17 to locate the defective chip and determine the
required action.
NOTE: If XX or YY is not documented in the following tables, this may mean
that more than one area contributed to the error condition. If this is the
case, the system adds the values of the failed data bits and displays the sum
in the XX or YY location.
Figures 5-1 and 5-2 show the memory chip locations for the COMPAQ PORTABLE II
Personal Computer System Boards - Version 1 and 2. For information on
removing and replacing memory chips contained on the system board, refer to
Chapter 7 in this guide.
Table 5-14. Version 1 System Board using 64K RAMs (0 - 256 Kbytes)
==============================================================================
XX = 00 (Bank 0)
------------------------------------------------------------------------------
Data Bit B = 0 B = 1
YY or ZZ Low High Required Action
-----------------------------------------------------------------------------
00 U37 U38 Replace memory chip
01 U30 U31 Replace memory chip
02 U25 U26 Replace memory chip
04 U21 U22 Replace memory chip
08 U16 U17 Replace memory chip
10 U14 U15 Replace memory chip
20 U9 U10 Replace memory chip
40 U5 U6 Replace memory chip
80 U1 U2 Replace memory chip
------------------------------------------------------------------------------
XX = 02 (Bank 1)
------------------------------------------------------------------------------
Data Bit B = 0 B = 1
YY or ZZ Low High Required Action
------------------------------------------------------------------------------
00 U41 U42 Replace system board
01 U51 U52 Replace system board
02 U51 U52 Replace system board
04 U51 U52 Replace system board
08 U51 U52 Replace system board

Compaq Portable II Specifications

General

Brand	Compaq
Model	Portable II
Category	Desktop
Language	English