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Checkpoint
No.
Description
D4h
Normal POST start
06h
DMA page register write/read test in-progress or
fail
08h
RAM refresh verification in-progress or failure
09h
1st 64K RAM test in-progress
0Ah
1st 64K RAM chip or data line failure - multi-bit
0Bh
1st 64K RAM odd/even logic failure
0Ch
1st 64K RAM address line failure
0Dh
1st 64K RAM parity test in_progress or failure
10h
1st 64K RAM chip or data line failure bit 0
20h
Slave DMA register test in-progress or failure
21h
Master DMA register test in-progress or failure
22h
Master interrupt mask register test in-progress
or fail
23h
Slave interrupt mask register test in-progress or
fail
25h
Interrupt vector loading in-progress
27h
Keyboard controller test in-progress or failure
28h
CMOS power-fail and checksum checks in-
progress
29h
CMOS config info validation in-progress
2Bh
Screen memory test in-progress or failure
2Ch
Screen initialization in-progress or failure
2Dh
Screen retrace tests in-progress or failure
2Eh
Search for video ROM in-progress
30h
Screen believed operable:
34h
Timer tick interrupt test in_progress or failure
35h
Shutdown test in_progress or failure
36h
Gate A20 failure
37h
Unexpected interrupt in protected mode
38h
RAM test in_progress or failure above address
0FFFFh
Error Messages
A-3
Summary of Contents for Extensa 450 Series
Page 1: ...Maintenance Manual Extensatm 450 Series Notebook Computers 9805725 0001 November 1995 ...
Page 12: ...Figure 1 2 Extensa 450 Series Features 1 4 General Description ...
Page 42: ...Figure 4 1 Notebook Functional Block Diagram 4 2 Theory ...
Page 71: ...Figure 6 5 Touchpad Removal Replacement 6 12 Field Service ...
Page 93: ...Connector Pinouts B 11 ...
Page 100: ...Printed in U S A ...