Send Data Block Db1; Parameter Definition Of Fb3 P_Send; Invoke Fb3 P_Send From Ob1 - Siemens SIMATIC S7 CP340 Programming Manual

4 ASCII protocol communication
Fig. 12: Send Data block DB1
3. Invoke Send Function block
The parameters of the send function block FB3 P_SEND of CP340 are set as in
the table below:
LADDR
DB_NO
DBB_NO
LEN
REQ
R
DONE
ERROR
STATUS
Table 3: Parameter definition of FB3 P_SEND
Fig. 13: Invoke FB3 P_SEND from OB1
4. Invoke Receive Function Block FB2 P_RCV from Libraries -> CP PtP -> CP340
and distribute instance data block DB2 to it. Set LADDR as the start logic address
256.
CP340/CP341/CP440/CP441 Communication and Programming
Entry-ID: 88867653, V1.0,
Start logic address in hardware configuration, which is 256 in this example
Send Data block number, which is 1(DB1) in this example
Start address of Send Data, which is 0(DB1.DBB0) in this example
Length of send data, which is 10 in this example
trigger bit of Send Data, rising edge trigger, which is M0.0 in this example
Cancel communication, which is not available in this example
send complete bit, which is TRUE if Send completes and has no error
error bit, TRUE indicating that it has an error
Status word, ID error code. See CP340 manual for related descriptions
02/2014
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