8 computing unit self-test prior to booting – Siemens PC 670 User Manual
Page 128
Fault Diagnosis
Release 04/02
6-8
Panel PC 670 Computing Unit, Equipment Manual
6.8
Computing Unit Self-Test Prior to Booting
After switching on the SIMATIC PC a self-test is initiated (POST = Power On Self
Test). If errors are detected during the POST, the corresponding sequence of
POST beeps (beep code) are issued. Each beep code consists of 2 x 2
sequences.
In addition, the individual test steps which the self-test executes, are issued on the
I/O port 80h.
Conversion table for the beep codes to hexadecimal representation:
Beeps
Hex Code
B
B
0
B
BB
1
B
BBB
2
B
BBBB
3
BB
B
4
BB
BB
5
BB
BBB
6
BB
BBBB
7
BBB
B
8
BBB
BB
9
BBB
BBB
A
BBB
BBBB
B
BBBB
B
C
BBBB
BB
D
BBBB
BBB
E
BBBB
BBBB
F
Example
B
BBB
BBB
B
Beeps
2
8
Hex Code
Test system memory
Meaning
Special codes
In addition to the beep codes listed below, there are also special codes:
3x short
INSERT button has been pressed during the system start:
The Onboard Device Installation is skipped. The Onboard
Graphic is used as the standard output.
1x long 8x short
Fault reading the MPI system information:
Contact your technical service department.
4x short
MPI EPROM was programmed for the first time.
1x long 5x short
Ethernet error: Contact your technical service department.