BC Series BIOS POST Codes

Code	LED Display	Description
40h		Preparing the virtual mode test. Verify from display memory next.
41h		Returned to POST after verifying from display memory. Preparing the descriptor tables next.
42h		The descriptor tables have been prepared. Entering virtual mode for the memory test next.
43h		Entered virtual mode. Enabling interrupts for diagnostics mode next.
44h		Interrupts are enabled if the diagnostics switch is on. Initializing data to check the memory wraparound at 0:0h next.
45h		Data has been initialized for the memory wraparound check. Checking for memory wraparound at 0:0h and finding the total system memory size next.
46h		The memory wraparound test has been done. The memory size calculation has been done. About to write memory test patterns.
47h		The memory test patterns were written to extended memory. Writing patterns in conventional memory (first 640 KB) next.
48h		The patterns to be tested were written to conventional memory. Finding the amount of memory below 1 MB next.
49h		The amount of memory below 1 MB was found and verified. Finding the amount of memory above 1 MB next.
4Ah		The amount of memory above 1 MB was found and verified. Performing the BIOS ROM data area check test next.
4Bh		The BIOS ROM data area check is done. Checking the Del key status and clearing the memory below 1 MB for a soft reset next.
4Ch		The memory below 1 MB has been cleared via a soft reset. Clearing the memory above 1 MB next.
4Dh		The memory above 1 MB has been cleared via a soft reset. Clearing the memory size next.
4Eh		The memory test has started. No soft reset was performed. About to display the first 64 KB memory test.
4Fh		The memory size display has started. This display is updated during the memory test. Running the sequential and random memory test.
50h		The test of memory below 1 MB completed. Adjusting the memory size for relocation and shadowing next.
51h		The memory size has been adjusted for memory relocation above 1 MB and shadowing options. The test of memory above 1 MB is next.
52h		The test of memory above 1 MB has completed. Preparing for real mode next.
53h		The CPU registers have been saved, including the memory size. Entering real mode next.
54h		Shutdown was successful and the CPU is in real mode. Restoring the registers saved during preparation for shutdown next.
55h		The registers have been restored. Disabling the Gate A20 address line next.
56h		The Gate A20 address line was disabled successfully. Checking the BIOS ROM data area next.
57h		The BIOS ROM data area check is partially completed. Completing the BIOS ROM data area check next.
58h		The BIOS ROM data area check has completed. Clearing the OHit DelO message next.
59h		The "Hit Del" message has been cleared. About to start the DMA and interrupt controller tests.