Siemens SIMATIC FM 353, Manual

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Programming the Technological Functions
6-16
FM 353 Stepper Drive Positioning Module
6ES7 353-1AH01-8BG0
Error evaluation
Communication errors or data interpretation errors on the FM are flagged in the
Binary Result (BR = 0) and by RET_VAL < 0; see job request status.
Possible errors are:
S Data transfer error (communication is not completed) during a transfer with SFC
58/59 “WR_REC / RD_REC”. The error code is made available in user data
block AW-DB, DBW66 (RET_VAL value of these internal SFCs) (job states 4, 5
and 6, see Table 6-2, see also Error List, Section 6.8).
S Data transferred with Write are checked for data errors by the module and inter-
preted. If a data error occurs, the checkback signal “Data error” (AW-DB,
DBX22.4) is set to TRUE in user data block AW-DB (message: “Write job ter-
minated with error”). The error number, read out via an internal job request, is
entered in user data block AW-DB, DBB94 and 95 (job status 3, Table 6-2).
You will find more information on data errors in the parameter initialization tool
under the menu command Debug > Error Evaluation and in Chapter 11.
Performance in the event of an error during the servicing of a Write request (does
not apply to single functions and commands):
S The Initiate signal is removed for the errored request and the Error signal (AW-
DB, DBX54.0 to 63.7) and Ready signal (AW-DB, DBX44.0 to 53.7) are set (job
request status, point 3, Table 6-2).
S The Initiate signal is also removed for all pending Write requests and the Error
signal set (job request status, point 4, Table 6-2).
S Any pending Read requests are serviced. The error code (AW-DB, DBW66) for
each request is re-set if another error occurs.
Performance in the event of an error during the servicing of a Read request :
S The Initiate signal is removed for the errored Read and the Error signal set (job
request status, point 5, Table 6-2).
S Any pending Read requests are serviced. The error code (AW-DB, DBW66) for
each request is re-set if another error occurs.
Performance in the event of an error during servicing of single functions and
commands :
S The Write request is not serviced in its entirety, and the Error signal is set (job
request status, point 4, Table 6-2).
S The function set/reset which led to initiation of the Write request is not acti-
vated.