Annex: Post-Codes
Beckhoff New Automation Technology
CB1052
page 83
Code
Description
49h
1. Determination of the entire memory size by revising the last 32-Bit double word of each 64k
memory segment.
2. Program “write allocation” at AMD K5-CPUs.
4Eh
1. Program MTRR at M1 CPUs
2. Initialise level 2-cache at CPUs of the class P6 and set the “cacheable range” of the random
access memory.
3. Initialise APIC at CPUs of the class P6.
4. Only for multiprocessor systems (MP platform): Setting of the “cacheable range” on the
respective smallest value (for the case of non-identical values).
50h
Initialise USB interface
52h
Testing of the entire random access memory and deleting of the extended memory (put on “0”)
55h
Only for multi processor systems (MP platform): Indicate the number of CPUs.
57h
1. Indicate the plug and play logo
2. First ISA plug and play initialising – CSN-assignment for each identified ISA plug and play
device.
59h
Initialise TrendMicro anti virus program code.
5Bh
(Optional:) Indication of the possibility to start AWDFLASH.EXE (Flash ROM programming)
from the hard disk.
5Dh
1. Initialise Variable/Routine Init_Onboard_Super_IO.
2. Initialise Variable/Routine Init_Onbaord_AUDIO.
60h
Release for starting the CMOS set-up (this means that before this step of POST, users are not
able to access the BIOS set-up).
65h
Initialising of the PS/2 mouse.
67h
Information concerning the size of random access memory for function call (INT 15h with AX-
Reg. = E820h).
69h
Enable level 2 cache
6Bh
Programming of the chip set register according to the BIOS set-up and auto-detection table.
6Dh
1. Assignment of resources for all ISA plug and play devices.
2. Assignment of the port address for onboard COM-ports (only if an automatic junction has
been defined in the setup).
6Fh
1. Initialising of the floppy controller
2. Programming of all relevant registers and variables (floppy and floppy controller).
73h
Optional feature:
Call of AWDFLASH.EXE if:
- the AWDFLASH program was found on a disk in the floppy drive.
- the shortcut ALT+F2 was pressed.
75h
Detection and installation of the IDE drives: HDD, LS120, ZIP, CDROM…
77h
Detection of parallel and serial ports.
7Ah
Co-processor is detected and enabled.
7Fh
1. Switch over to the text mode, the logo output is supported.
- Indication of possibly emerged errors. Waiting for keyboard entry.
- No errors emerged, respective F1 key was pressed (continue):
Deleting of the EPA- or own logo.
82h
1. Call the pointer to the “chip set power management”.
2. Load the text font of the EPA-logo (not if a complete picture is displayed)
3. If a password is set, it is asked here.
83h
Saving of the data in the stack, back to CMOS.
84h
Initialising of ISA plug and play boot drives (also Boot-ROMs)
85h
1. Final initialising of the USB-host.
2. At network PCs (Boot-ROM): Construction of a SYSID structure table
3. Backspace the scope presentation into the text mode
4. Initialise the ACPI table (top of memory).
5. Initialise and link ROMs on ISA cards
6. Assignment of PCI-IRQs
7. Initialising of the advanced power management (APM)
8. Set back the IRQ-register.
