Siemens SIMATIC S5 Manual page 193

Error Diagnostics
Table 5-6. Error-Detecting Programs of the Operating System (continued)
Byte 1*
45 Bit test of the external µP8032 RAM
46 µP8032 function test
Test of the internal µP8032 RAM
47
48 SSP function test
49 Operating system EPROM test (64 Kbytes)
50 User EPROM test (8, 16, 32 Kbytes depending on control program)
51 Assigning a page of the parallel interface
53 Job header, common to all parallel interface jobs
54 Central error routine for evaluating and storing an error and activating the error
response
55 Self-test; organizes, together with the test manager, the "high-value component
test" to be processed in time slices
56 Short test; organizes a "high-value" test before the S5-115F enters the RUN mode.
This test is not executed in time slices.
58...63 Auxiliary programs with access to pages of the parallel interface
74 Assigning information about number and type of connected modules to data fields;
comparison with configuration
99 Synchronization of the subunits
* Byte 1 in error record
5-12
Function of the Program Section
S5-115F Manual
EWA 4NEB 811 6149-02