Download Q Corresponding Ethernet Interface Module User`s Manual (Basic)

7 FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)
MELSEC-Q
POINT
In order to start up the interrupt program, the "Network parameters Ethernet
interrupt setting" and "PLC parameter" – "Intelligent function module interrupt
pointer setting" are required.
(2) Control method
The control method when the interrupt program starts up is explained using fixed
buffer No. 2 and the area corresponding to connection No. 2 as an example.
The interrupt settings with GX Developer for reading receive data using the
interrupt program example below is illustrated in the screen display shown in
(1).
<<Data receiving using the dedicated BUFRCVS instruction (interrupt program)>>
FEND
SM400
I50
Receive data
• [D200]: Word count for receive data stored
• From [D201]: Receive data
Z.BUFRCVS "U0" K2 D200
IRET
Initial processing Open processing
Initial normal completion signal X19
Data receiving
Response sending
1)
2)
Open completion signal
(Address: 5000H [b1])
4)
BUFRCVS instruction
6)
ACK
(only TCP)
Response
Data receiving
I50 interrupt processing
3)
Cycle
Sequence program
Interrupt program
7 - 10
Scan
ACK
(only TCP)
5)
Cycle
END
processing
Scan
Scan
END
processing
Data receive processing
7 - 10