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MELSEC-Q
4 FUNCTIONS
4.2.2 Extended service mode (MODE E)
This is the mode for communicating with the slave station by allocating any I/O area of
the QJ71PB92D buffer memory to each slave station.
Because the I/O area size can be set for each slave station, an empty space is not
produced in the buffer memory of QJ71PB92D. Therefore, the data can be read
from/write to the continuous area of the PLC CPU.
The area of allocation for each slave station is set using the GX Configurator-DP.
The area of allocation in the input and output areas for each station is 0 to 244 bytes (0
to 122 words).
The set number of slave stations 1 to 60.
When an area of 244 bytes (max) is allocated for each station, up to seven stations
can be set up.
After the communication start is completed (X00=ON), the allocated area data
equivalent to an amount of specified number of bytes is transmitted to each slave
station.
Before the communication is started or when it is interrupted, the I/O data is not
updated.
Input area
QJ71PB92D
buffer memory
1st station input data
2nd station input data
3rd station input data
PROFIBUS-DP
network
Slave station
(Station No. 1)
Input data
(32 bytes)
Output data
(32 bytes)
Output area
1st station output data
2nd station output data
3rd station output data
Slave station
(Station No. 2)
Input data (16 bytes)
Output data (16 bytes)
Slave station
(Station No. 3)
Input data
(32 bytes)
Output data
(32 bytes)
960 (320
H
)
16 ( 10
H
)
0 ( 0
H
)
24 ( 18
H
)
976 (330
H
)
984 (338
H
)
