Mitsubishi Electric MELSEC iQ-R16MTCPU - Data Communication between CPU Modules in the Multiple CPU System; Used Memory

1 MULTIPLE CPU SYSTEM
1.3 Data Communication Between CPU Modules in the Multiple CPU System
31
1
1.3 Data Communication Between CPU Modules in the
Multiple CPU System
Data transfer is performed between CPU modules in the Multiple CPU system. Data can be written and read between CPUs
through communication by refreshing or by direct access. Data communication methods are shown below.
Refer to the following for details on data communication between CPU modules (data communication via CPU buffer memory/
fixed scan communication area).
MELSEC iQ-R CPU Module User's Manual (Application)
Used memory
Data communication between CPU modules uses the CPU buffer memory.
CPU buffer memory configuration
The CPU buffer memory configuration is shown below.
*1 To transfer data using the fixed scan communication area, specify fixed scan communication area settings at GX Works3. Refer to the
following for details on fixed scan communication area settings.
MELSEC iQ-R CPU Module User's Manual (Application)
Communication method Application Details
Data communication via CPU
buffer memory
Use to transfer data based on
the timing of the respective CPU
modules.
CPU modules transmitting data write to the self CPU buffer memory. CPU modules
receiving data read from the self CPU buffer memory of the CPU module (other CPU)
from which the data was transmitted.
Data communication via fixed
scan communication area
Use to transfer data based on
the timing between CPU
modules.
CPU modules transmitting data write to the self CPU fixed scan communication area
(transmission area). CPU modules receiving data read from the self CPU fixed scan
communication area (receipt area) of the CPU module to which the data was transmitted.
Memory Communication method Details Area size
CPU buffer memory Communication by direct
access
Data reading and writing is performed for the self CPU or
other CPU area.
PLC CPU: 512k words
Motion CPU: 2M words
Refresh area Communication by refresh Data communication is performed by refreshing at END
processing.
Fixed scan
communication area
*1
Communication by direct
access
Data reading and writing is performed for the self CPU fixed
scan communication area, and self CPU and other CPU data
transfer is performed in fixed scan communication cycles.
Changes can be made within an
overall range of 0 to 24k words. The
transmission area per module can
be set in the 0 to 12k word range.
Refresh area Communication by refresh Refresh is performed in fixed scan communication cycles.
0
User setting area
0
to
to
to
to
to
2047
2048
524287
524288
999999
1000000
2097151
CPU buffer memory
System area
System area
User setting area
User setting area
Refresh(END) area
Occupies the points for refresh(END) only.
When refresh(END) is not used, this can be
used as user setting area.
(Fixed scan communication
area setting points - 1)
Refresh(I45 executing)
area
CPU buffer memory
(Fixed scan communication area)
Occupies the points for refresh(I45 executing) only.
When refresh(I45 executing) is not used, this
can be used as user setting area.