Siemens Simatic S7-300 CPU 31xC Series Installation And Operating Instructions Manual page 155

Sample program
Below you will see a small sample program for data exchange between DP master and DP
slave. The addresses used in the example are found in the table above.
In the DP slave CPU
L 2 //Data preparation in DP slave
T MB 6
L IB 0
T MB 7
L MW 6 // Forward data to DP master
T PQW 310
CALL SFC 14
LADDR:=W#16#D
RET_VAL:=MW 20
RECORD:=P#M30.0 byte 20
L MB 30
L MB 7
+ I
T MW 100
S7-300, CPU 31xC and CPU 31x: Installation
Operating Instructions, Edition 08/2004, A5E00105492-05
//Receive data from
//DP master
//Received
data//continue
processing
8.5 Commissioning PROFIBUS DP
In the DP master CPU
L PIB 222
T MB 50
L PIB 223
L B#16#3
+ I
T MB 51
L 10
+ 3
T MB 60
CALL SFC 15
LADDR:= W#16#0
RECORD:= P#M60.0 Byte 20
RET_VAL:=MW 22
Commissioning
//continued processing
of//received data in DP
master
//Data preparation in DP
master
//Send data to
//DP slave
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