Compaq 1692, 1687, 1685, 1694, 1683, 1688, 1693, 1690 manual Running Post, Power-On Self Test Post

Presario 1600 Series

Models: 1683, 1685, 1687, 1688, 1690, 1692, 1693, and 1694

Before You Begin	Specifications	Parts Catalog
Removal Sequence	Troubleshooting	Battery Operations
		Index
Product Description	Pin Assignments

Preliminary

Steps

Clearing the

Power-On

Password

Power-On Self Test (POST)

Compaq

Diagnostics

Diagnostic

Error Codes

Solving

Minor

Problems

Contacting

Compaq

Support

Running POST

To run POST, complete the following steps:

●Turn off the computer, then turn on the computer.

●If POST does not detect any errors, the computer will not beep. This indicates successful completion of POST test. POST has run successfully and boots from the hard drive (or from a bootable diskette if one is installed in the diskette drive).

●If POST detects errors, the errors are indicated by screen and/or audible messages. Refer to "Power-On Self-Test (POST) Codes" in the tables for a list of POST codes and their relevant descriptions.

If the system is not functioning well enough to run POST, or if the NOTE: display is not functioning well enough to show POST error messages,

refer to the Troubleshooting tables.

The following routines are sorted by their test point NOTE: numbers assigned in the BIOS code. Their actual orders

as executed during POST can be quite different.

Code		Beeps	POST Routine Description
02h			Verify Real Mode
03h			Disable Non-Maskable Interrupt (NM)
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
			boost
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	1-3-4-2		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
30th	1-4-1-1		RAM failure on data bits xxxx*of high byte
			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
50Eh			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 UserPatchI
66h			Configure advanced cache registers
67h			Initialize Multi Processor APIC
68h			Enable external and CPU cache
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			Reinitialize onboard I/O ports
87h			Configure Motherboard 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
81h			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 shot 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 back up 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 interrupts

Code	Beeps	For Boost 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 interrupts vectors
F1h		Initialize Run Time Clock
F2h		Initialize Video
F3h		Initialize beeper
F4h		Initialize boot
F5h		Clear Huge segment
F6h		Boot to Mini DOS
F7h		Boot to Full DOS