Mitsubishi Electric MELSEC-L SERIES Basic User Manual page 131

(2) No procedure
The following is the receive process performed in the fixed buffer number 2 area for the connection number 2.
Initial normal completion
signal X19
Open completion signal
(address: 5000 [b1])
H
BUFRCVS instruction
In interrupt process
Program
Confirm the normal completion of the initial process. (Initial normal completion signal (X19): ON)
1
Establish a connection between the E71 and the connected device and confirm the normal completion of the
2
open process of the connection number 1.
Receive data from the destination.
3
• Request the CPU module to start up the interrupt program.
The interrupt program starts up. Execute the BUFRCVS instruction to read the receive data length and
4
receive data from the fixed buffer number 1.
End the interrupt program to restart the main program.
5
Initial Open
process process Receiving data
1
2
Cycle
END
Scan
process
CHAPTER 12 COMMUNICATIONS USING A FIXED BUFFER
4
ACK
(TCP only)
3
Cycle
Interrupt process
Scan
5
END
Scan
process
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