4 - 16
4 FUNCTIONS
MELSEC-QnA
4.5 Communication in Compound Systems
The overview of the communication where the remote I/O station, remote device
station and local station coexist in the system.
SET Yn0
1
SET Yn8
2
5
Programmable controller CPU
Master station
Remote I/O station (station No. 1)
Buffer memory
Remote input (RX)
Remote output (RY)
Send area to
local station No. 3
Send area to
local station No. 4
Remote register
(RWw)
Remote register
(RWr)
Data link startup
by EEPROM
parameters
8
13
FROM
FROM
FROM
FROM
TO
TO
TO
TO
TO
TO
TO
FROM
FROM
FROM
Input
Output
3
7
11
12
12
Refresh instruction
Receive area
from remote
I/O station No. 1
Receive area
from remote
device station No. 2
Receive area from
local station No. 3
Receive area from
local station No. 4
Send area to remote
I/O station No. 1
Send area to remote
device station No. 2
Unusable
(station No. 1)
Send area to remote
device station No. 2
Send area to
local station No. 3
Send area to
local station No. 4
Unusable
(station No. 1)
Receive area
from remote
device station No. 2
Receive area from
local station No. 3
Receive area from
local station No. 4
13
13
8
8
6
6
6
6
5
5
5
3
3
3