5 Power-On Self-Test and Error Messages

Order in Which the Tests are Performed

Checkpoint

POST Routine Description

Code

 

 

 

52h

Test keyboard

 

 

54h

Set key click if enabled

 

 

56h

Enable keyboard

 

 

59h

Initialize POST display service

 

 

5Ah

Display prompt “Press F2 to enter SETUP”

 

 

5Bh

Disable CPU cache

 

 

5Ch

Test RAM between 512 and 640 KB

 

 

60h

Test extended memory

 

 

62h

Test extended memory address lines

 

 

64h

Jump to UserPatch1

 

 

66h

Configure advanced cache registers

 

 

67h

Initialize Multi Processor APIC

 

 

68h

Enable external and CPU caches

 

 

69h

Setup System Management Mode (SMM) area

 

 

6Ah

Display external L2 cache size

 

 

6Ch

Display shadow-area message

 

 

6Eh

Display possible high address for UMB recovery

 

 

70h

Display error messages

 

 

72h

Check for configuration errors

 

 

74h

Test real-time clock

 

 

76h

Check for keyboard errors

 

 

7Ah

Test for key lock on

 

 

7Ch

Set up hardware interrupt vectors

 

 

7Eh

Initialize coprocessor if present

 

 

80h

Disable onboard Super I/O ports and IRQs

 

 

89