B-3
:2Dh The video ROM has returned control to BIOS POST. Performing any required
processing after the video ROM had control
23h Reading the 8042 input port and disabling the MEGAKEY Green PC feature
next. Making the BIOS code segment writable and performing any necessary
configuration before initializing the interrupt vectors.
24h The configuration required before interrupt vector initialization has completed.
Interrupt vector initialization is about to begin.
25h Interrupt vector initialization is done. Clearing the password if the POST DIAG
switch is on.
27h Any initialization before setting video mode will be done next.
28h Initialization before setting the video mode is complete. Configuring the
monochrome mode and color mode settings next.
2Ah Bus initialization system, static, output devices will be done next, if present. See
the last page for additional information.
2Eh Completed post-video ROM test processing. If the EGA/VGA controller is not
found, performing the display memory read/write test next.
2Fh The EGA/VGA controller was not found. The display memory read/write test is
about to begin.
30h The display memory read/write test passed. Look for retrace checking next.
31h The display memory read/write test or retrace checking failed. Performing the
alternate display memory read/write test next.
32h The alternate display memory read/write test passed. Looking for alternate
display retrace checking next.
34h Video display checking is over. Setting the display mode next.
37h The display mode is set. Displaying the power on message next.
38h Initializing the bus input, IPL, general devices next, if present. See the last page
of this chapter for additional information.
39h Displaying bus initialization error messages. See the last page of this chapter for
additional information.
3Ah The new cursor position has been read and saved. Displaying the Hit <DEL>
message next.
3Bh The Hit <DEL> message is displayed. The protected mode memory test is about
to start.
40h Preparing the descriptor tables next.
42h The descriptor tables are prepared. Entering protected mode for the memory test
next.
43h Entered protected mode. Enabling interrupts for diagnostics mode next.
44h Interrupts enabled if the diagnostics switch is on. Initializing data to check
memory wraparound at 0:0 next.
45h Data initialized. Checking for memory wraparound at 0:0 and finding the total
system memory size next.
46h The memory wraparound test is done. Memory size calculation has been done.
Writing patterns to test memory next.
Checkpoint Code Description