BIOS POST Tone Error Codes

What is all that beep, beep, supposed to mean?
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This material is presented only as a description of how I go about working on a system. It is not meant to encourage unqualified personnel to attempt computer repair. In any event, you assume all responsibility and liability for injury or damage.

Anthony Olszewski
COPYRIGHT 1996

AMI BIOS Tone POST Codes -- Fatal Errors
TONE CONDITION
1 shortDRAM refresh
2 short Parity circuit
3 short Base 64K RAM
4 short System timer
5 short Processor
6 short Keyboard controller gate A20
7 short Virtual mode exception
8 short Display memory read/write test
9 short ROM BIOS checksum
10 short CMOS shutdown read/write
11 short Cache memory

AMI BIOS Tone POST Codes -- Non-Fatal Errors
TONE CONDITION
1 long, 3 short Conventional/extended memory
1 long, 8 short Display/retrace test

Phoenix BIOS Tone POST Codes -- Fatal Errors
TONE CONDITION
None CPU register test
None First 64K RAM test
None Interrupt vector loading proceeding
None CMOS power failure/checksum calculation
None Display configuration validation proceeding
None Display running with video ROM
None Display functional
None Mononchrome display functional
None CGA display functional
1-1-3 CMOS write/read
1-1-4 ROM BIOS checksum
1-2-1 Programmable interval timer
1-2-2 DMA Initialization
1-2-3 DMA page register write/read
1-3-1 RAM refresh verification
1-3-3 First 64K RAM chip or data line
1-3-4 First 64K RAM odd/even logic
1-4-1 Address line first 64K RAM
1-4-2 Parity failure first 64K RAM
2-1-1 Bit 0, first 64K RAM
2-1-2 Bit 1, first 64K RAM
2-1-3 Bit 2, first 64K RAM
2-1-4 Bit 3, first 64K RAM
2-2-1 Bit 4, first 64K RAM
2-2-2 Bit 5, first 64K RAM
2-2-3 Bit 6, first 64K RAM
2-2-4 Bit 7, first 64K RAM
2-3-1 Bit 8, first 64K RAM
2-3-2 Bit 9, first 64K RAM
2-3-3 Bit 10, first 64K RAM
2-3-4 Bit 11, first 64K RAM
2-4-1 Bit 12, first 64K RAM
2-4-2 Bit 13, first 64K RAM
2-4-3 Bit 14, first 64K RAM
2-4-4 Bit 15, first 64K RAM
3-1-1 Slave DMA register
3-1-2 Master DMA register
3-1-3 Master interrupt mask register
3-1-4 Slave interrupt mask register
3-2-4 Keyboard controller
3-3-4 Display initialization
3-4-1 Display retrace
3-4-2 Search for video ROM proceeding

Phoenix BIOS POST Tone Codes -- Non-Fatal Errors
TONE CONDITION
4-2-1 Timer tick interrupt test
4-2-2 Shutdown test
4-2-3 Gate A20 Failure
4-2-4 Unexpected interrupt in protected moe
4-3-1 RAM test (address failure >FFFFh)
4-3-3 Interval timer channel 2
4-3-4 Real time clock
4-4-1 Serial Port
4-4-2 Parallel Port
4-4-3 Math Co-processor test
1-1-2* System board select
1-1-3* Extender CMOS RAM
*audio code pattern preceded by low pitched tone

IBM POST Tone Codes
TONE CONDITION
NONE System board, power supply
1 short System passed all tests
2 short Display error
continuous System board, power supply
1 long, 1 short System board
1 long, 2 short Video adapter
1 long, 3 short EGA
3 long 3270 keyboard card