Reducing The Link Device Refresh Time; Concept Of Refresh Range (Points) - Mitsubishi Electric Q12DCCPU-V User Manual

5
ACCESS VIA NETWORK MODULES

(3) Reducing the link device refresh time

The link device refresh time can be reduced by decreasing the number of refresh
points for the C Controller module. To decrease the refresh points, modify the refresh
and network range assignment parameter settings and use the direct access method
for accessing link devices.
(a) Concept of refresh range (points)
Range set by
refresh
parameters
POINT
Within the range set with refresh parameters in the <<Parameter settings>> tab of
MELSECNET/H utility, the areas set in the network range assignment are
refreshed.
C Controller module
Internal link
device buffers
Range to be
actually
refreshed
Applicable
as internal
memory
Applicable
as internal
memory
Applicable
as internal
memory
Figure 5.33 Concept of refresh range
The range from the first address to the last address is set by default in the refresh
parameter setting.
(To bring the setting back to the default, click the Default button on the Refresh
parameter settings screen activated from the <<Parameter settings>> tab of
MELSECNET/H utility.)
5.3 MELSECNET/H Module Access Function
5.3.5 Link data transfer processing time specifications
MELSECNET/H module
Network range
assignment parameter
Station
Link device
No.1
refresh
(Empty)
Station
Link device
No.2
refresh
(Empty)
Link device
Station
refresh
No.3
1
2
3
Range set by
network range
assignment
4
5
6
7
8
5
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