Mitsubishi Electric MELSEC Q Series User Manual page 29

(4) Multiple CPU system setting
For control in the multiple CPU system, it is necessary to set up the "Number of mounted CPU modules" and the
"Control CPU" with PLC parameter for all CPU modules mounted on the main base unit.
User's Manual (Function Explanation, Program Fundamentals) for the CPU module used
(5) Access range of multiple CPU system
In the multiple CPU system, the access ranges are different between the controlled module and the non-con-
trolled module.
(a) Controlled module
The multiple CPU system's control CPU can refresh the I/O data of controlled modules and read/write the
buffer memory data of intelligent function modules in the same way as in a single CPU system.
(b) Non-controlled module
It is possible to access non-controlled modules in the following ways.
• Refreshing the input for I/O modules, I/O composite module and intelligent function modules
(the PLC parameter's multiple CPU setup is necessary.)
• Reading the intelligent function module's buffer memory.
• Downloading the output data from the output module, the I/O composite module and the intelligent func-
tion modules.
(the PLC parameter's multiple CPU setup is necessary.)
However, it is not possible to access non-controlled modules in the following ways.
• Outputting data to output modules, I/O composite module and intelligent function modules.
• Writing data into the intelligent function module's buffer memory.
(c) Range of access to other station's CPU module
To access to a CPU module on other station from GX Developer, access can be made through a network mod-
ule controlled by any CPU module in the multiple CPU system.
When other station has multiple CPUs, specifying the CPU No. allows access to the desired CPU.
User's manual for each network module
1 - 4
CPU 0 1 2 3 4
1 2 1 1 1 1
Readable with CPU module 2.
Readable with CPU module 1.
Figure 1.3 Access to non-controlled module
Slot number
5 6 7
Control CPU setting
2 2 2