Fb Cam_Diag (Fb 2) - Siemens S7-300 Operating Instructions Manual

7.4

FB CAM_DIAG (FB 2)

Tasks
Use FB CAM_DIAG to read the diagnostic buffer of the module and make it available for
display on an operator control and monitoring system or for a programmed evaluation.
Call
The function block must be called cyclically. It is not permitted to initiate a second call in an
interrupt OB. At least two calls (cycles) are required to completely execute this function.
The function block reads the diagnostic buffer when a new entry in the diagnostic buffer is
indicated by checkback signal DIAG = 1. After the diagnostic buffer is read, DIAG is set to 0
by the module.
Data used
● Diagnostic DB:
Jobs
You can read the diagnostic buffer whether or not there is a new entry by setting the
DIAGRD_EN trigger bit. After reading the diagnostic buffer, the trigger bit is set to 0.
Parameters
Parameter
DB_NO
RETVAL
Startup
There is no startup processing associated with the function block.
FM 352 electronic cam controller
Operating Instructions, 05/2011, A5E01071724-03
The module address must be entered in the diagnostic DB. The newest entry in the
diagnostics buffer is written in the DIAG[1] structure and the oldest entry is written in the
DIAG[4] structure.
Declaration
INPUT
OUTPUT
Data type Description
INT Number of the diagnostic DB
INT Return value
Programming the FM 352
7.4 FB CAM_DIAG (FB 2)
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