Checkpoint | Description |
|
|
31 | Allocate memory for ADM module and uncompress it. Give control to ADM module |
| for initialization. Initialize language and font modules for ADM. Activate ADM |
| module. |
|
|
33 | Initializes the silent boot module. Set the window for displaying text information. |
|
|
37 | Displaying |
| specific information. |
|
|
38 | Initializes different devices through DIM. See DIM Code Checkpoints section for |
| more information. USB controllers are initialized at this point. |
|
|
39 | Initializes |
|
|
3A | Initialize RTC date/time. |
|
|
3B | Test for total memory installed in the system. Also, Check for DEL or ESC keys to |
| limit memory test. Display total memory in the system. |
|
|
3C | Mid POST initialization of chipset registers. |
|
|
40 | Detect different devices (Parallel ports, serial ports, and coprocessor in CPU, ... |
| etc.) successfully installed in the system and update the BDA, EBDA…etc. |
|
|
50 | Programming the memory hole or any kind of implementation that needs an |
| adjustment in system RAM size if needed. |
|
|
52 | Updates CMOS memory size from memory found in memory test. Allocates |
| memory for Extended BIOS Data Area from base memory. Programming the |
| memory hole or any kind of implementation that needs an adjustment in system |
| RAM size if needed. |
|
|
60 | Initializes |
|
|
75 | Initialize |
|
|
78 | Initializes IPL devices controlled by BIOS and option ROMs. |
|
|
7A | Initializes remaining option ROMs. |
|
|
7C | Generate and write contents of ESCD in NVRam. |
|
|
84 | Log errors encountered during POST. |
|
|
85 | Display errors to the user and gets the user response for error. |
|
|
87 | Execute BIOS setup if needed / requested. Check boot password if installed. |
|
|
8C | Late POST initialization of chipset registers. |
|
|
8D | Build ACPI tables (if ACPI is supported) |
|
|
8E | Program the peripheral parameters. Enable/Disable NMI as selected. |
|
|
90 | Late POST initialization of system management interrupt. |
|
|
A0 | Check boot password if installed. |
|
|
A1 | |
|
|
A2 | Takes care of runtime image preparation for different BIOS modules. Fill the free |
| area in F000h segment with 0FFh. Initializes the Microsoft IRQ Routing Table. |
| Prepares the runtime language module. Disables the system configuration display if |
| needed. |
|
|
A4 | Initialize runtime language module. Display boot option popup menu. |
|
|
A7 | Displays the system configuration screen if enabled. Initialize the CPU’s before |
| boot, which includes the programming of the MTRR’s. |
|
|
A8 | Prepare CPU for OS boot including final MTRR values. |
|
|
A9 | Wait for user input at config display if needed. |
|
|
AA | Uninstall POST INT1Ch vector and INT09h vector. Deinitializes the ADM module. |
|
|
AB | Prepare BBS for Int 19 boot. |
|
|
AC | End of POST initialization of chipset registers. |
|
|
58 | Chapter 4 |