4 ASCII protocol communication
CP340/CP341/CP440/CP441 Communication and Programming
Entry-ID: 88867653, V1.0, 02/2014
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4. Invoke Receive Function Block FB7 P_RCV_RK from Libraries -> CP PtP ->
CP341 and distribute instance data block DB7 to it. Set LADDR as the start
logic address 256 in hardware configuration.
5. Create receive data block DB10
Fig. 29: Receive data block DB10
6. Invoke receive function block
The parameters of the receive function block FB8 FB7 P_RCV_RK of CP341
are set as in the table below:
LADDR
Start logic address in hardware configuration, which is
256 in this example
DB_NO
Send Data block number, which is 10(DB10) in this
example
DBB_NO
Start address of Send Data, which is 0(DB10.DBB0) in
this example
LEN
Length of receive data, which is MW2 in this example.
This value is not 0 only in the current cycle when data are
received. The length of received data may be determined
by checking the MW4 value.
EN_R
Enable receive bit, which is M0.1 in this example.
R
Cancel communication, which is not available in this
example
NDR
Receive complete bit, which is TRUE if Receive
completes and has no error
ERROR
error bit, TRUE indicating that it has an error
STATUS
status word, ID error code. See CP341 manual for related
descriptions
Other
parameters
Irrelevant to ASCII communication protocol, and not
available in this example
Table 6: Parameter definition of FB7 P_RCV_RK