Arche Legacy BIOS POST Codes
- 00 - Call the interrupt 19 boot loader
- 01 - Disable the NMI and test CPU registers
- 02 - Verify the BIOS ROM checksum (32KB at F8000h)
- 03 - Initialize the keyboard controller and CMOS RAM communication
- 04 - Disable the DMA and PIT; test the CMOS RAM interrupt
- 05 - Reset the video controller
- 06 - Test the 8254 programmable interrupt timer
- 07 - Test delta count timer channel 2 (speaker)
- 08 - Test delta count timer channel 1 (memory refresh)
- 09 - Test delta count timer channel 0 (system timer)
- 0A - Test parity circuit and turn on refresh
- 0B - Enable parity check and test system timer
- 0C - Test refresh trace link toggle
- 0D - Test refresh timing synchronization
- 10 - Disable cache and shadow memory; test the 64KB base memory
- 11 - Perform 64KB memory read/write test
- 12 - Initialize interrupt vector table in lower 1KB of RAM
- 14 - Test CMOS RAM shutdown register...disable DMA and interrupt controllers
- 15 - Test CMOS RAM battery and checksum
- 16 - Test for floppy drive, based on CMOS setup...initialize monochrome video
- 17 - Initialize CGA video
- 18 - Clear the parity status (if any)
- 19 - Test for EGA/VGA video BIOS at C0000h and pass control
- 1A - Return from video ROM
- 1B - Test primary video adapter...test video memory
- 1C - Test secondary video adapter...test video memory
- 1D - Compare CMOS settings to video adapter
- 1E - Set video mode according to CMOS settings
- 20 - Display CMOS RAM read/write errors and halt
- 21 - Set cursor and call interrupt 10 to display status message
- 22 - Display power on message; 386 BIOS; check if CPU speed is 25Mhz or 33Mhz
- 23 - Read new cursor position
- 24 - Display AMI copyright message at the bottom of the screen
- 25 - Test shadow RAM
- F0 - Shadow RAM test failed
- 30 - Ready to enter protected mode
- 31 - Enter protected mode (A20 gate) and enable timer interrupt (IRQ 0)
- 32 - Get memory size above 1MB
- 33 - Get memory size below 640KB
- 34 - Test memory above 1MB
- 35 - Test memory below 1MB
- 37 - Clear memory below 1MB
- 38 - Clear memory above 1MB
- 39 - Use CMOS shutdown byte and return to real mode
- 3A - Test 64KB read/write
- 3B - Test RAM below 1MB and show the area being tested
- 3C - Test RAM above 1MB and show the area being tested
- 3D - RAM test complete OK
- 3E - Ready to return to real mode
- 3F - Back in real mode
- 40 - Disable A20 gate
- 41 - Check for AMI copyright message in ROM
- 42 - Display the AMI copyright message, if found
- 43 - Test cache memory; Clear Esc message
- 4E - Process shutdown 1; Return to real mode
- 4F - Restore interrupt vectors and data in BIOS RAM area
- 50 - Test DMA controller
- 51 - Initialize DMA controller
- 52 - Test the DMA controller with patterns
- 54 - Test DMA controller latches
- 55 - Initialize and enable DMA controllers 1 and 2
- 56 - Initialize 8259 programmable interrupt controllers
- 57 - Test 8259 programmable interrupt controllers and setup interrupt mask registers
- 61 - Check DDNIL status bit and display message
- 70 - Perform keyboard (BAT) basic assurance test
- 71 - Program keyboard to AT type
- 72 - Disable keyboard and initialize keyboard circular buffer
- 73 - Display message and initialize floppy controller and drive
- 74 - Attempt to access the floppy drive
- 75 - If the CMOS RAM is good, check and initialize the hard disk controller and drive
- 76 - Attempt to access the hard disk drive
- 77 - Shuffle and internal error codes
- 79 - Check CMOS RAM battery and checksum...clear parity status
- 7A - Compare size of base/extended memory to CMOS information
- 7B - Unknown AMI function
- 7C - Display AMI copyright
- 7D - Set AT memory expansion bit
- 7E - Verify the ROM contains and AMI copyright
- 7F - Clear the Del message from the display...check if Del was pressed
- 80 - Locate option ROM at C800h to DE00h and pass control to any found
- 81 - Return from option ROM and initialize timer and data area
- 82 - Setup parallel and serial ports
- 83 - Test for math coprocessor
- 84 - Check if keyboard is locked
- 85 - Display any soft error messages
- 86 - Test for option ROM at E0000h
- A0 - Error found in 256KB or 1MB RAM IC in lower 640KB
- A1 - Base 64KB random access and data pattern test (only in 386APR and Presto 386SX BIOS)
- A9 - Initialize on board VGA controller (Presto 386SX BIOS)
- B0 - Error in 256KB RAM IC in 640KB
- B1 - Base 64KB random access and data pattern test (only in Presto 386SX BIOS)
- E0 - Return to real mode and initialize base 64KB RAM (Presto)
- E1 - Initialize 640KB RAM (Presto)
- EF - Configuration memory error - can't find memory
- F0 - Test shadow RAM from 04000h