HP XM600 - Kayak - 128 MB RAM Technical Reference Manual page 125

Checkpoint
Beeps
Code
F1h
F2h
F3h
F4h 1
F5h
F6h
F7h
1.
If the BIOS detects error 2C, 2E, or 30 (base 512K RAM error), it displays an additional word-bitmap
(xxxx) indicating the address line or bits that failed.For example:
"2C 0002" means line 1 (bit one set) has failed.
"2E 1020" means data bits 12 and 5 (bits 12 and 5 set) have failed in the lower 16 bits.
The BIOS also sends the bitmap to the port-80 LED display. It first displays the checkpoint code,
followed by a delay, the high-order byte, another delay, and then the low-order byte of the error. It
repeats this sequence continuously.
POST Routine Description
Initialize Run Time Clock
Initialize video
Initialize System Management Mode
Output one beep before boot
Boot to Mini DOS
Clear Huge Segment
Boot to Full DOS
6 Tests and Error Messages
Order in Which POST Tests Are Performed
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