Balluff BIS M-370-000-A02, Manual, Page: 176 / 198

PROFINET INTERFACE
169
10
10.3 DATA EXCHANGE
The Master Profinet is usually a PLC (Siemens S7 or others) but it could be a PC based
device as well. The Profinet Controller is always Slave in the Profinet network.
PLC
RFID
Controller
RFID
Controller
RFID
Controller
RFID
Controller
RFID
Controller
Profinet Network
Profinet Master
Profinet Slaves
Profinet Slaves
Figure 73 - Profinet IO Network Diagram
Basically two shared memory areas (Exchange Areas) are used to exchange information
between the SLAVE and the MASTER, both devices provide information to each other.
INPUT
AREA
OUTPUT
AREA
PLC BIS M-628-075-
Write Read
Write Read
Exchange Areas
Master Slave
Figure 74 - Profinet Communication
– Data Exchange Areas Diagram
Input and Output areas always refer to the Master: this means that the Controller writes to
the Input buffer and the PLC writes to the Output buffer.
The dimension of the exchange areas can be set to different values by the PLC through the
GSD file: the Profinet Controller allows up to
248 bytes as a combined total of the Input
and Output Areas .
NOTE
For further information regarding Fieldbus interfacing including
downloadable support files, go to the HMS website at
http://www.anybus.com, choose the link to the support page, select the
Anybus-CompactCom product type and then your network type .