Mitsubishi Electronics Q172DCPU Home Security System User Manual


 
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2 MULTIPLE CPU SYSTEM
2.3.2 Multiple CPU high speed transmission
(1) Multiple CPU high speed transmission
Multiple CPU high speed transmission is a function for fixed cycle data
transmission between Multiple CPUs (Multiple CPU high speed transmission
cycle is 0.88ms.).
Secure data transmission is possible without effecting the PLC CPU scan time or
Motion CPU main cycle because the data transmission and execution of PLC
program and Motion SFC program can be executed with parallel processing.
High speed response between multiple CPUs is realized by synchronizing the
Multiple CPU high speed transmission cycle with Motion CPU operation cycle.
The following methods of data transmission exist between Multiple CPUs for
Multiple CPU high speed transmission.
• Multiple CPU area device method
Directly set the Multiple CPU high speed transmission area by Multiple CPU
area device (U
\G ) in the program.
• Automatic refresh method
Refresh the internal devices of each CPU by automatic refresh via "Multiple
CPU high speed transmission area".
(a) Multiple CPU area device method
CPU shared memory
(User setting area
(Note-1)
)
SM400
U3E0\
G10110.5
MOV W1
U3E0\
G10100
SM400
2)
U3E0\G10000
U3E0\G10010
U3E0\G10100
U3E0\G10110
U3E0\G10000
U3E0\G10010
U3E0\G10100
U3E0\G10110
5)
1)
4)
U3E0\
G10010.1
MOV W0
U3E0\
G10000
END
CPU No.1 (PLC CPU) CPU No.2 (Motion CPU)
CPU shared memory
(User setting area
(Note-1)
)
PLC program Motion SFC program
3)
6)
G0
U3E0\G10010.1
F0
W0=U3E0\G10010
G1
U3E0\G10110.5
F1
W1=U3E0\G10110
CPU No.1
transmitting
data
CPU No.1
transmitting
data
Multiple CPU high speed
transmission in 0.88ms cycle
1), 4) : Write data in the user setting area
(Note-1)
by the instruction that uses the Multiple CPU area device.
3), 6) : Read data from the user setting area
(Note-1)
by the instruction that uses the Multiple CPU area device.
2), 5) : Transmit the contents of user setting area
(Note-1)
to the other CPU with by Multiple CPU high speed transmission in 0.88ms cycle.
Note-1: The area composed in the Multiple CPU high speed transmission area.
(Refer to Section "(3) Memory configuration of Multiple CPU high speed transmission area".)