General POST Errors

General POST Errors `
1xx Systemboard Errors
2xx Main Memory Errors
3xx Keyboard Errors
5xx Color Monitor Error
6xx Floppy Disk Controller Errors
14xx Printer Errors
17xx Hard Disk Controller Errors
86xx Mouse Errors

Specific BIOS Beeps

AMIBIOS (American Megatrend)

Except for beep code #8, these codes are always fatal.
· 1 beep Refresh failure
· 2 beeps Parity error
· 3 beeps Base 64K memory failure
· 4 beeps Timer not operational
· 5 beeps Processor error
· 6 beeps 8042 - gate A20 failure
· 7 beeps Processor exception interrupt error
· 8 beeps Display memory read/write failure
· 9 beeps ROM checksum error
· 10 beeps CMOS shutdown register read/write error
· 11 beeps Cache memory bad

· For 1 beep, 2 beeps, or 3 beeps try reseating the memory first. If the error still occurs, replace the memory with known good chips.

· For 4 beeps, 5 beeps, 7 beeps, or 10 beeps the system board must be sent in for repair.

· For 6 beeps try reseating the keyboard controller chip. If the error still occurs, replace the keyboard chip. If the error persists, check parts of the system relating to the keyboard, e.g. try another keyboard, check to see if the system has a keyboard fuse.

· 8 beeps indicate a memory error on the video adapter. Replace the video card or the memory on the video card.

· 9 beeps indicate faulty BIOS chip(s). It is not likely that this error can be corrected by reseating the chips. Consult the motherboard supplier or an AMI product distributor for replacement part(s).

· If no beeps are heard and no display is on the screen, The first thing to check is the power supply. Connect an LED to the POWER LED connection on the motherboard. If this LED lights and the drive(s) spin up then the power supply will usually be good.

· Next, inspect the motherboard for loose components. A loose or missing CPU, BIOS chip, Crystal Oscillator, or Chipset chip will cause the motherboard not to function.

· Next, eliminate the possibility of interference by a bad or improperly set up I/O card by removing all card except the video adapter. The system should at least power up and wait for a drive time-out. Insert the cards back into the system one at a time until the problem happens again. When the system does nothing, the problem will be with the last expansion card that was put in.

· If the above suggestions fail to cause any change in the disfunction of the system, the motherboard must be returned for repair.

Phoenix

POST Tasks and Beep Codes

When you turn on or reset an IBM- compatible PC, the BIOS first performs a number of tasks, called the Power- On- Self- Test (POST). These tasks test and initialize the hardware and then boot the Operating System from the hard disk.

At the beginning of each POST task, the BIOS outputs the test- point error code to I/ O port 80h. Programmers and technicians use this code during trouble shooting to establish at what point the system failed and what routine was being performed. Some motherboards are equipped with a seven- segment LED display that displays the current value of port 80h. For production boards which do not contain the LED display, you can purchase an installable "Port 80h" card that performs the same function. If the BIOS detects a terminal error condition, it issues a terminal- error beep code (See following), attempts to display the error code on upper left corner of the screen and on the port 80h LED display, and halts POST. It attempts repeatedly to write the error to the screen. This attempt may "hash" some CGA displays. If the system hangs before the BIOS can process the error, the value displayed at the port 80h is the last test performed. In this case, the screen does not display the error code.

Copyright © 1997 by Phoenix Technologies Ltd.
All Rights Reserved
Phoenix Technologies Ltd.
Desktop Division
135 Technology Drive
Irvine, CA 92618

Terminal POST Errors
There are several POST routines that require success to finish POST. If they fail, they issue a POST Terminal Error and shut down the system. Before shutting down the system, the error handler issues a beep code signifying the test point error, writes the error to port 80h, attempts to initialize the video, and writes the error in the upper left corner of the screen (using both mono and color adapters).

The routine derives the beep code from the test point error as follows:
1. The 8- bit error code is broken down to four 2- bit groups.
2. Each group is made one- based (1 through 4) by adding 1.
3. Short beeps are generated for the number in each group.
Example:
Testpoint 16h = 00 01 01 10 = 1- 2- 2- 3 beeps

POST Task Routines
The following is a list of the Test Point codes written to port 80h at the start of each routine, the beep codes issued for terminal errors, and a description of the POST routine. Unless otherwise noted, these codes are valid for PhoenixBIOS 4.0 Release 6.0.

NOTE: The following routines are sorted by their test point numbers assigned in the BIOS code. Their actual order as executed during POST can be quite different.

Code Beeps POST Routine Description
02h Verify Real Mode
03h Disable Non- Maskable Interrupt (NMI)
04h Get CPU type
06h Initialize system hardware
08h Initialize chipset with initial POST values
09h Set IN POST flag
0Ah Initialize CPU registers
0Bh Enable CPU cache
0Ch Initialize caches to initial POST values
0Eh Initialize I/ O component
0Fh Initialize the local bus IDE
10h Initialize Power Management
11h Load alternate registers with initial POST values
12h Restore CPU control word during warm boot
13h Initialize PCI Bus Mastering devices
14h Initialize keyboard controller
16h 1- 2- 2- 3 BIOS ROM checksum
17h Initialize cache before memory autosize
18h 8254 timer initialization
1Ah 8237 DMA controller initialization
1Ch Reset Programmable Interrupt Controller
20h 1- 3- 1- 1 Test DRAM refresh
22h 1- 3- 1- 3 Test 8742 Keyboard Controller
24h Set ES segment register to 4 GB
26h Enable A20 line
28h Autosize DRAM
29h Initialize POST Memory Manager
2Ah Clear 512 KB base RAM
2Ch 1- 3- 4- 1 RAM failure on address line xxxx *
2Eh 1- 3- 4- 3 RAM failure on data bits xxxx * of low byte of memory bus
2Fh Enable cache before system BIOS shadow
30h 1- 4- 1- 1 RAM failure on data bits xxxx * of high byte of memory bus
32h Test CPU bus- clock frequency
33h Initialize Phoenix Dispatch Manager
36h Warm start shut down
38h Shadow system BIOS ROM
3Ah Autosize cache
3Ch Advanced configuration of chipset registers
3Dh Load alternate registers with CMOS values
42h Initialize interrupt vectors
45h POST device initialization
46h 2- 1- 2- 3 Check ROM copyright notice
48h Check video configuration against CMOS
49h Initialize PCI bus and devices
4Ah Initialize all video adapters in system
4Bh QuietBoot start (optional)
4Ch Shadow video BIOS ROM
4Eh Display BIOS copyright notice
50h Display CPU type and speed
51h Initialize EISA board
52h Test keyboard
54h Set key click if enabled
58h 2- 2- 3- 1 Test for unexpected interrupts
59h Initialize POST display service
5Ah Display prompt "Press F2 to enter SETUP"
5Bh Disable CPU cache
5Ch Test RAM between 512 and 640 KB
60h Test extended memory
62h Test extended memory address lines
64h Jump to UserPatch1
66h Configure advanced cache registers
67h Initialize Multi Processor APIC
68h Enable external and CPU caches
69h Setup System Management Mode (SMM) area
6Ah Display external L2 cache size
6Bh Load custom defaults (optional)
6Ch Display shadow- area message
6Eh Display possible high address for UMB recovery
70h Display error messages
72h Check for configuration errors
76h Check for keyboard errors
7Ch Set up hardware interrupt vectors
7Eh Initialize coprocessor if present
80h Disable onboard Super I/ O ports and IRQs
81h Late POST device initialization
82h Detect and install external RS232 ports
83h Configure non- MCD IDE controllers
84h Detect and install external parallel ports
85h Initialize PC- compatible PnP ISA devices
86h Re- initialize onboard I/ O ports.
87h Configure Motheboard Configurable Devices (optional)
88h Initialize BIOS Data Area
89h Enable Non- Maskable Interrupts (NMIs)
8Ah Initialize Extended BIOS Data Area
8Bh Test and initialize PS/ 2 mouse
8Ch Initialize floppy controller
8Fh Determine number of ATA drives (optional)
90h Initialize hard- disk controllers
91h Initialize local- bus hard- disk controllers
92h Jump to UserPatch2
93h Build MPTABLE for multi- processor boards
95h Install CD ROM for boot
96h Clear huge ES segment register
97h Fixup Multi Processor table
98h 1- 2 Search for option ROMs. One long, two short beeps on checksum failure
99h Check for SMART Drive (optional)
9Ah Shadow option ROMs
9Ch Set up Power Management
9Dh Initialize security engine (optional)
9Eh Enable hardware interrupts
9Fh Determine number of ATA and SCSI drives
A0h Set time of day
A2h Check key lock
A4h Initialize Typematic rate
A8h Erase F2 prompt
AAh Scan for F2 key stroke
ACh Enter SETUP
AEh Clear Boot flag
B0h Check for errors
B2h POST done - prepare to boot operating system
B4h 1 One short beep before boot
B5h Terminate QuietBoot (optional)
B6h Check password (optional)
B9h Prepare Boot
BAh Initialize DMI parameters
BBh Initialize PnP Option ROMs
BCh Clear parity checkers
BDh Display MultiBoot menu
BEh Clear screen (optional)
BFh Check virus and backup reminders
C0h Try to boot with INT 19
C1h Initialize POST Error Manager (PEM)
C2h Initialize error logging
C3h Initialize error display function
C4h Initialize system error handler
C5h PnPnd dual CMOS (optional)
C6h Initialize notebook docking (optional)
C7h Initialize notebook docking late
C8h Force check (optional)
C9h Extended checksum (optional)
D2h Unknown interrupt

Code Beeps For Boot Block in Flash ROM
E0h Initialize the chipset
E1h Initialize the bridge
E2h Initialize the CPU
E3h Initialize system timer
E4h Initialize system I/ O
E5h Check force recovery boot
E6h Checksum BIOS ROM
E7h Go to BIOS
E8h Set Huge Segment
E9h Initialize Multi Processor
EAh Initialize OEM special code
EBh Initialize PIC and DMA
ECh Initialize Memory type
EDh Initialize Memory size
EEh Shadow Boot Block
EFh System memory test
F0h Initialize interrupt vectors
F1h Initialize Run Time Clock
F2h Initialize video
F3h Initialize System Management Mode
F4h 1 Output one beep before boot
F5h Boot to Mini DOS
F6h Clear Huge Segment
F7h Boot to Full DOS

* If the BIOS detects error 2C, 2E, or 30 (base 512K RAM error), it displays an additional word- bitmap ( xxxx ) indicating the address line or bits that failed. For example, "2C 0002" means address line 1 (bit one set) has failed.
"2E 1020" means data bits 12 and 5 (bits 12 and 5 set) have failed in the lower 16 bits. Note that error 30 cannot occur on 386SX systems because they have a 16 rather than 32- bit bus. The BIOS also sends the bitmap to the port- 80 LED display. It first displays the check point code, followed by a delay, the high- order byte, another delay, and then the low- order byte of the error. It repeats this sequence continuously.

Award

When a personal computer is first turned on, the BIOS tests and configures various components to ensure that they are operating correctly. This operation is called POST (power-on self test). If the BIOS detects any problems during this testing phase, it will attempt to continue to start the computer. However, if the problems are severe, the BIOS may be forced to halt the system.

When an error is detected, the BIOS program will:

Display the error to the screen, if possible.

Generate a POST beep code using the computer's internal speaker if it cannot access the display adaptor.

Provide a POST code output that can be read using a special hardware tool.

Beep Codes
The only AwardBIOS beep code indicates that a video error has occurred and the BIOS cannot initialize the video screen to display any additional information. This beep code consists of a single long beep followed by two short beeps. Any other beeps are probably a RAM (Random Access Memory) problem.

Screen Error Messages
The following messages are examples of messages including errors detected by the BIOS during POST and a description of what they mean and/or what you may do to correct the error.

BIOS ROM checksum error - System halted	The checksum of the BIOS code in the BIOS chip is incorrect, indicating the BIOS code may have become corrupt. Contact your system dealer to replace the BIOS.
CMOS battery failed	The CMOS battery is no longer functional. Contact your system dealer for a replacement battery.
CMOS checksum error - Defaults loaded	Checksum of CMOS is incorrect, so the system loads the default equipment configuration. A checksum error may indicate that CMOS has become corrupt. This error may have been caused by a weak battery. Check the battery and replace if necessary.
CPU at nnnn	Displays the running speed of the CPU.
Display switch is set incorrectly	The display switch on the motherboard can be set to either monochrome or color. This message indicates the switch is set to a different setting than indicated in Setup. Determine which setting is correct, and then either turn off the system and change the jumper, or enter Setup and change the VIDEO selection.
Press ESC to skip memory test	The user may press Esc to skip the full memory test.
Floppy disk(s) fail	Cannot find or initialize the floppy drive controller or the drive. Make sure the controller is installed correctly. If no floppy drives are installed, be sure the Diskette Drive selection in Setup is set to NONE or AUTO.
HARD DISK initializing Please wait a moment	Some hard drives require extra time to initialize.
HARD DISK INSTALL FAILURE	Cannot find or initialize the hard drive controller or the drive. Make sure the controller is installed correctly. If no hard drives are installed, be sure the Hard Drive selection in Setup is set to NONE.
Hard disk(s) diagnosis fail	The system may run specific disk diagnostic routines. This message appears if one or more hard disks return an error when the diagnostics run.
Keyboard error or no keyboard present	Cannot initialize the keyboard. Make sure the keyboard is attached correctly and no keys are pressed during POST. To purposely configure the system without a keyboard, set the error halt condition in Setup to HALT ON ALL, BUT KEYBOARD. The BIOS then ignores the missing keyboard during POST.
Keyboard is locked out - Unlock the key	This message usually indicates that one or more keys have been pressed during the keyboard tests. Be sure no objects are resting on the keyboard.
Memory Test:	This message displays during a full memory test, counting down the memory areas being tested.
Memory test fail	If POST detects an error during memory testing, additional information appears giving specifics about the type and location of the memory error.
Override enabled - Defaults loaded	If the system cannot boot using the current CMOS configuration, the BIOS can override the current configuration with a set of BIOS defaults designed for the most stable, minimal-performance system operations.
Press TAB to show POST screen	System OEMs may replace the Phoenix Technologies' AwardBIOS POST display with their own proprietary display. Including this message in the OEM display permits the operator to switch between the OEM display and the default POST display.
Primary master hard disk fail	POST detects an error in the primary master IDE hard drive.
Primary slave hard disk fail	POST detects an error in the secondary master IDE hard drive.
Resuming from disk, Press TAB to show POST screen	Phoenix Technologies offers a save-to-disk feature for notebook computers. This message may appear when the operator re-starts the system after a save-to-disk shut-down. See the Press Tab & message above for a description of this feature.
Secondary master hard disk fail	POST detects an error in the primary slave IDE hard drive.
Secondary slave hard disk fail	POST detects an error in the secondary slave IDE hard drive.

Post Codes

POST Codes are hexadecimal codes generated by the BIOS during the POST operation. These codes may be monitored on a special hardware "Post card" which displays them using a two digit alphanumeric display.

ISA Post codes are output to port address 80h.

EISA Post codes are typically output to port address 300h.

Code (hex)	Name	Description
co	Turn off Chipset Cache	OEM Specific-Cache control
1	Processor Test 1	Processor status (1FLAGS) Verification.Tests the following processor status flags: carry, zero, sign, overflow.
1	Processor Test 1	The BIOS sets each flag, verifies they are set, then turns each flag off and verifies it is off.
2	Processor Test 2	Read/Write/Verify all CPU registers except SS, SP, and BP with data pattern FF and 00.
3	Initialize Chips	Disable NMI, PIE, AIE, UEI, SQWV.
		Disable video, parity checking, DMA.
		Reset math coprocessor.
		Clear all page registers, CMOS shutdown byte.
		Initialize timer 0,1, and 2, including set EISA timer to a known state.
		Initialize DMA controllers 0 and 1.
		Initialize interrupt controllers 0 and 1.
		Initialize EISA extended registers.
4	Test Memory Refresh Toggle	RAM must be periodically refreshed to keep the memory from decaying. This refresh function is working properly.
5	Blank video, Initialize keyboard	Keyboard controller initialization.
6	Reserved
7	Test CMOS Interface and Battery Status	Verifies CMOS is working correctly, detects bad battery.
BE	Chipset Default Initialization	Program Chipset registers with power on BIOS defaults
CI	Memory presence test	OEM Specific-Test to size on-board memory.
C5	Early Shadow	OEM Specific-Early Shadow enable for fast boot.
C6	Cache presence test	External cache size detection.
8	Setup low memory	Early chip set initialization.
		Memory presence test.
		OEM chip set routines.
		Clear low 64K of memory.
		Test first 64K memory.
9	Early Cache Initialization	Cyrix CPU initialization.
9	Early Cache Initialization	Cache initialization.
A	Setup Interrupt Vector Table	Initialize first 120 interrupt vectors with SPURIOUS_INT_HDLR and initialize INT 00h-1Fh according to INT_TBL.
B	Test CMOS RAM Checksum	Test CMOS RAM checksum, if bad, or insert key pressed, load defaults.
C	Initialize Video Interface	Detect type of keyboard controller (optional).
C	Initialize Video Interface	Set NUM_LOCK status.
D	Initialize Video Interface	Detect CPU clock.
		Read CMOS location 14h to find out type of video in use.
		Detect and Initialize Video Adapter.
E	Test Video Memory	Test video memory, write sign-on message to screen.
E	Test Video Memory	Setup shadow RAM – Enable shadow according to Setup.
F	Test DMA	BIOS checksum test.
F	Controller 0	Keyboard detect and initialization.
10	Test DMA Controller 1	Test DMA Controller 1.
11	Test DMA Page Registers	Test DMA Page Registers.
12-13	Reserved
14	Test Timer Counter 2	Test 8254 Timer 0 Counter 2.
15	Test 8259-1 Mask Bits	Verify 8259 Channel 1 masked interrupts by alternately turning off and on the interrupt lines.
16	Test 8259-2 Mask Bits	Verify 8259 Channel 2 masked interrupts by alternately turning off and on the interrupt lines
17	Test Stuck 8259’s Interrupt Bits	Turn off interrupts then verify no interrupt mask register is on.
18	Test 8259 Interrupt Functionality	Force an interrupt and verify the interrupt occurred.
19	Test Stuck NMI	Verify NMI can be cleared.
1A		Display CPU clock.
1B-1E	Reserved
1F	Set EISA Mode	If EISA non-volatile memory checksum is good, execute EISA initialization.
		If not, execute ISA tests an clear
		EISA mode flag.
		Test EISA Configuration Memory
		Integrity (checksum & communication interface).
20	Enable Slot 0	Initialize slot 0 (System Board).
21-2F	Enable Slots 1-15	Initialize slots 1 through 15.
30	Size Base and Extended Memory	Size base memory from 256K to 640K and extended memory above 1MB.