SICK AFM60 PROFINET - Acyclic Process Data Handling

3 PRODUCT DESCRIPTION
24
OPERATING INSTRUCTIONS | AFS60/AFM60 PROFINET 8015078/145N/2019-05-24 | SICK STEGMANN
Subject to change without notice
3.5 Acyclic process data
The acyclic process data are processed in parallel and in addition to the cyclic process
data transmission. The acyclic process data are normally not used continuously, but
only as required. They are used to configure the encoder or for requesting its status
information.
The acyclic process data essentially comprise the services Read and Write with which
the master can obtain read or write access to data blocks in the PROFINET slave.
The access to the acyclic process data in the AFS60/AFM60 PROFINET has been
implemented in accordance with the PROFIdrive profile. For the access to these data
the profile uses the client-server model. Communication is undertaken using the
Request parameter and the Response parameter.
A write or read task for one or more parameters is transmitted in the Request
parameter. The Response parameter then contains the response to a request.
The profile provides various indices for the data access:
Record Data Object
MAP index
Start-up configuration
BF00h
Start-up configuration vendor specific
1000h
Base mode parameter access
B02Eh
I&M0 parameters
AFF0h
Table 23: Indices for the data access
The parameters described in this section are communicated via the index B02Eh,
which is stipulated for the base mode parameters as per PROFIdrive.
A Request is transmitted from the master to the slave. Transmission is via write access
to the index B02Eh. The encoder interprets the Request parameter and makes
available the data. These data (Response parameter) must also be read via the same
index.
Figure 5: Request and Response
System function blocks
On the Siemens S7 control systems two system function blocks can be used for the
acyclic communication:
 SFB52 RDREC (read record)
 SFB53 WRREC (write record)
The functions then contain, among other items, the Request and Response parameters
as well as the index B02Eh as function parameters.
A Request parameter is transmitted to the encoder using WRREC. The reply, Response
parameter, is then read using the function RDREC.
Response
Output of the data via B02Eh
Request
Read/write the data via B02Eh
PLC
Encoder