5 Power-On Self-Test and Error Messages

Order in Which the Tests are Performed

Checkpoint

POST Routine Description

Code

 

 

 

81h

Late POST device initialization

 

 

82h

Detect and install external RS 232 ports

 

 

83h

Configure non-MCD IDE controllers

 

 

84h

Detect and install external parallel ports

 

 

85h

Initialize PC-compatible PnP ISA devices

 

 

86h

Re-initialize onboard I/O ports

 

 

87h

Configure Motherboard Configurable Devices

 

 

88h

Initialize BIOS Data Area

 

 

89h

Enable Non-Maskable Interrupts (NMIs)

 

 

8Ah

Initialize Extended BIOS Data Area

 

 

8Bh

Test and initialize PS/2

 

 

8Ch

Initialize floppy controller

 

 

8Fh

Determine number of ATA drives

 

 

90h

Initialize hard disk controllers

 

 

91h

Initialize local-bus hard disk controllers

 

 

92h

Jump to UsersPatch2

 

 

93h

Build MPTABLE for multi-processor boards

 

 

94h

Disable A20 address line (Rel. 5.1 and earlier)

 

 

95h

Install CD ROM for boot

 

 

96h

Clear huge ES segment register

 

 

97h

Fixup Multi Processor table

 

 

99h

Check for SMART drive

 

 

9Ah

Shadow option ROMs

 

 

9Ch

Set up Power Management

 

 

9Eh

Enable hardware interrupts

 

 

90