Dell 3250, Руководство по эксплуатации продукта

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POST Error Codes and Messages
In order to indicate progress through BIOS POST, and in special cases where errors are
encountered during BIOS POST, there are three common mechanisms employed by the server
system BIOS. The first method is to display port 80/81 codes to an I
2
C adapter connected to the
main board. The second common method is the use of beep codes, encoded beep sequences emitted
by the PC speaker when an error is encountered. Beep codes are employed only before the display
screen is enabled, and generally indicate fatal errors. Beep codes are coupled with special port 80
error codes. The final method is to display an error message to the display screen.
North and South Port 80/81 Cards
This port 80 card is a custom device attached to I
2
C ports in two different places on the server. One
port 80 device serves the north flash ROM and the other serves the south flash ROM.
POST Codes
POST Codes Module Map
The system employs a novel POST code scheme. POST codes assigned make use of the fact that
the server system utilizes port 80h and 81h. This gives the system 16 bits to encode. The following
rules apply to the POST code encoding, except bit 14 and 15 encoding for SALB, SALC and
SALF:
•
Bit 15: 1 – Itanium-based code being executed, 0 – IA-32 code being executed
•
Bit 14: 1 – system stopped due to known failure, 0 – progress indication
For SALB, SALC and SALF modules:
•
Bit 15: 1 – Itanium-based code being executed
0 – system stopped due to known failure
•
Bit 14: not used, always 0 All other module bits remain unmodified.
•
Bit 13: 1 – fault or trap (no change in module numbers)
0 – normal execution
In case of fault or trap, only bit 13 is set and other bits are left modified. This allows detection
of which module produces the fault.
•
Bit 12: Reserved
•
Bit 11-4: Module number
•
Bit 3-0: Sub module number
The module number and sub-module number are separated by a 4-bit boundary that allows quick
decoding. The module number identifies the major module such as memory, PCI, ACPI, etc. The
sub module number identifies the sub function such as SPD read in progress, ECC error, and
DIMM mismatch for memory module.