beautypg.com

7 process data transfer, Process data transfer, Process data transfer 7 – Lenze EMF2133IB User Manual

Page 45: 7process data transfer

background image

Process data transfer

7

l

45

EDSMF2133IB EN 5.0

7

Process data transfer

request

response

2133PFB008

Fig. 7−1

PROFIBUS process data transfer

PROFIBUS transmits parameter data and process data between the host (master) and the
controllers connected to the bus (slaves). Depending on their time−critical nature, the data
are transmitted via different communication channels.

ƒ

Process data are transmitted via the process data channel.

ƒ

Process data serve to control the drive controller.

ƒ

The transmission of process data is time−critical.

ƒ

Process data are cyclically transferred between the host and the controllers
(continuous exchange of current input and output data).

ƒ

The host can directly access the process data. In the PLC, for instance, the data are
directly assigned to the I/O area.

ƒ

With the function module a maximum of 10 process data words (16 bits/word) can
be exchanged in each direction.

ƒ

Process data are not stored in the controller.

ƒ

Process data are, for instance, setpoints, actual values, control words and status
words.

)

Note!

Observe the direction of the information flow!

ƒ

Process input data (Rx data):
– Process data from controller (slave) to host (master)

ƒ

Process output data (Tx data):
– Process data from host (master) to controller (slave)