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4-10 Maintenance and Troubleshooting
Beep Codes
During boot up, the computer performs a series of POST (Power On Self Test) routines. A
beep code may appear when an error is detected. There are fatal and nonfatal errors. The
fatal errors include BIOS, CMOS, DMA, RAM, video, and keyboard controller errors. The
nonfatal errors include timer tick interrupt, shutdown test, unexpected interrupt in protected
mode, gate A20, RAM test, interval timer channel 2 test, clock, serial and parallel port test,
math co-processor, system board select, and extended CMOS RAM.
The following table provides a description of the beep codes.
Table 4-2 Beep Code Descriptions
Beeps
Error Message
Description
1
Refresh Failure
The memory refresh circuitry on the system
board is faulty.
2
Parity Error
Parity error in the first 64 KB of memory.
3
Base 64 KB Memory Failure
Memory failure in the first 64 KB.
4
Timer Not Operational
Memory failure in the first 64 KB of
memory, or Timer 1 on the system board is
not functioning.
5
Processor Error
The CPU on the system board generated
an error.
6
8042 - Gate A20 Failure
The keyboard controller (8042) may be
bad. The BIOS cannot switch to protected
mode.
7
Processor Exception Interrupt
Error
The CPU generated an exception interrupt.
8
Display Memory Read/Write Error
The system graphics adapter is either
missing or its memory is faulty. This is not
a fatal error.
9
ROM Checksum Error
ROM checksum value does not match the
value encoded in BIOS.
10
CMOS Shutdown Register
Read/Write Error
The shutdown register for CMOS RAM
failed.
Summary of Contents for Direction T-Series
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