6 - 6
MELSEC-F
FIXED BUFFER COMMUNICATION (WITH THE PROCEDURE EXIST
CONTROL METHOD)
6
6 - 6
6.3 Receiving Control Method
This section explains the control method when the Ethernet module receives data
from an external device.
6.3.1 Receive processing with the main program
This section explains the receiving process to be performed with the main program,
using an example in which the fixed buffer No. 2 and the area corresponding to
connection No. 2.
• For FX
3U
/FX
3UC
Series PLCs
Program example for the unit No. 0
M8000
[BMOV
D1000
D101
]
[MOV
D101
]
[MOV
D100
]
[MOV
H2
]
[=
D100
H1
]
[=
D100
H8
]
[INCP
D102
]
]
[END
* <<Storing the data received from the external device to the fixed buffer No.2 in D1000 and later>>
* <Receiving status
* <Obtaining received word count
* <Read of received data
* <Write of receiving completion
* <Receiving failed
>
>
>
>
>
U0
G1611
U0
G2688
U0
G1611
U0
G2689
Receive abnormal processing
User applications are described at the area enclosed with .
ACK
(only TCP)
5)
Response
ACK
(only TCP)
2)
Data receiving
W
0002
H
Initial processing normal
completion
OPEN/CLOSE instruction status
BFM #1602=0005
H
Received word count and
received data written to PLC
FROM instruction
Fixed buffer received status and
received completion message
BFM #1611
R
0001
H
R
0004
H
(Success)/0008
H
(Error issued)
Initial
processing
Open
processing
Response
sending
Data
receiving
1)
3)
4)
6)