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.