12
APPLICATION FUNCTIONS
12
- 16
12.1 Transient Transmission Function
12.1.4 SEND/RECV function
12.1.4 SEND/RECV function
The SEND/RECV function sends/receives data to/from other station's programmable
controller using the MELSEC data link library function.
This function supports the SEND/RECV instruction of link dedicated instruction.
POINT
For details of the functions, refer to the following manual.
MELSEC Data Link Library Reference Manual
(1) SEND function
The SEND function sends data from the own station to the specified channel of the
specified station using the mdSend/mdSendEx function.
Two execution types, "arrival acknowledgment" and "no arrival acknowledgment", are
available for the SEND function. When sending data with "no arrival acknowledgment"
execution type, all stations in group numbers can be specified as target stations.
POINT
(1) An error occurs when data are sent to the same channel which is being used.
(2) Only an even number byte can be specified for a send data size.
(3) Logical station numbers cannot be specified.
(4) Even if the process of data send is completed normally with "arrival
acknowledgment" execution type, data may not be received when the target
station is a board. For details, refer to the RECV function.
CPU module
RECV
Target station
Channel 1
Channel 2
Channel 3
Channel 4
Channel 5
Channel 6
Channel 7
Channel 8
Board
Driver
User application
Channel 1
Channel 2
Channel 3
Channel 4
Channel 5
Channel 6
Channel 7
Channel 8
main() {
mdOpen( 151, -1, &path );
mdSendEx( path, 1, 1, ,
);
mdClose( path );
}
Board
Driver
User application
Channel 1
Channel 2
Channel 3
Channel 4
Channel 5
Channel 6
Channel 7
Channel 8
CPU module
RECV
Target station
Channel 1
Channel 2
Channel 3
Channel 4
Channel 5
Channel 6
Channel 7
Channel 8
Error
main() {
mdOpen( 151, -1, &path );
mdSendEx( path, 1, 1,
);
mdClose( path );
}
,
