Mitsubishi Electric MELSEC Q Series Reference Manual page 193

5 PARAMETER SETTINGS
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POINT
When the intelligent function module buffer memory is located in several different
areas, the forwarding parameter between devices are convenient when combining
them for access.
Master
CPU module
module
READ
(1) The buffer memory is refreshed to remote I/O module link register W by the
automatic refreshing of the intelligent function module parameters. (Refer to
Section 5.2.1 (4).)
(2) The buffer memory is transferred from link register W to data register D by
forwarding parameter between devices.
(3) The remote master station can read and write the remote I/O module data
register D using 1 read/write instruction.
If the remote master station makes direct access to the intelligent function module
buffer memory using REMFR/REMTO instructions, the REMFR/REMTO
instructions will implement several cycles of the buffer memory area.
Master
CPU module module
REMFR
REMFR
REMFR
Remote I/O module
Link register W
MELSECNET/H
2)
Data register D
3)
Remote I/ O module
MELSECNET/ H
MELSEC-Q
Intelligent function
module
Buffer Buffer
memory memory
1)
Intelligent function
module
Buffer Buffer
memory memory
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