Point-To-Point Link
S5-95U, Second Serial Interface
2.4
Program Example of Point-To-Point Link
In this section, the structure of a PLC program for a point-to-point link is explained in detail.
Example:
The program example can be used for any communication partner both as point-to-point master and
slave.
The example can be used for an S5-95U as point-to-point master if slave number 0 is parameterized
in DB1 and destination number 1 is used in FB100 for transmission ( following program example).
The example can be used for an S5-95U as a point-to-point slave if slave number 1 is parameterized
in DB1 and destination number 0 is used in FB100 for transmission.
The S5-95U is to receive data from the communication partner and send data to the communication
partner.
Proceed as follows:
Establish the ready state at the communication partner (parameterized as slave 1).
Switch the S5-95U on and carry out
”
PLC overall reset
”
(PLC mode: STOP).
Parameterize the point-to-point link in DB1 of the S5-95U as described below.
Program the individual blocks as described below.
Transfer DB1 and the PLC program to the S5-95U.
Switch the mode selector of the PLC to RUN.
For the program structure of the program example please refer to the following diagram
( Figure 2-7).
Figure 2-7 Program Structure Point-To-Point Link
OB1
FB100 is
called
cyclically
FB100
Receive data
and
Send data
DB100
from DW 80
Send mailbox
DB100
from DW 40
Receive
mailbox
DB1
assigns
parameters
of point-to-point
link to system
data words
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EWA 4NEB 812 6095-02
