9
DEVICE EXPLANATION
9.13 Convenient Usage of Devices
9.13.1 Global devices and local devices
9
- 100
9
Device Explanation
10
CPU Module Processing
Time
11
Procedure for Writing
Program to CPU Module
AppendicesIndex
(2) Local devices
Local devices are used independently by the programs.
The use of local devices permits programming of multiple "independent execution"
programs without regard to other programs.
However, the local device data can be stored into the standard RAM and memory
card only.
(a) Devices that can be used as local devices
The following devices can be used as local devices.
• internal relays (M)
• edge relays (V)
• timers (T, ST)
• counters (C)
• data registers (D)
(b) Saving and restoration of local device file
Programs used as local devices exchange the local device file data stored in the
memory card with the data in the device memory of CPU module.
Therefore the scan time is extended by this data exchange time.
Diagram 9.92 Using the local devices
Diagram 9.93 Saving and restoration of local device file
Y12
M7000
Y11
M7000
ON/OFF
M7000
ON/OFF
M7000
If local devices are designated as M7000 or later, they can be used independently in
each program executing M7000 or later.
Program B
Program A
M7000 ON/OFF data
M7000 ON/OFF data
For program A
For program B
Internal relay
Internal relay
Standard RAM/Memory card
CPU module
Y12
M7000
Y11
M7000
ON/OFF
M7000
ON/OFF
M7000
If local devices are designated as M7000 or later, they can be used independently in
each program executing M7000 or later.
Program B
Program A
M7000 ON/OFF data
M7000 ON/OFF data
For program A
For program B
Internal relay
Internal relay
Standard RAM/Memory card
CPU module
Local devices
Program A Program B Program C
Local devices Local devices
Restored
Saved
Restored
Saved
Restored
Sequence program
For
program A
For
program B
For
program C
For
program A
For
program B
For
program C
For
program A
For
program B
For
program C
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