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8.2 Access to AnS/A Series Corresponding Special Function Module
8
COMMUNICATION WITH INTELLIGENT FUNCTION
MODULE
8.2 Access to AnS/A Series Corresponding Special Function Module
(1) Effects of quicker access to the special function module
Note2
The Q series CPU module can process at higher speed, taking shorter time to scan.
When the FROM/TO instruction is frequently executed for the special function module
during a short scan, the processing of the target special function module may not be
normally terminated.
In this case, match the FROM/TO instruction execution interval to the processing
time/conversion time using the timer, constant scan, etc. of the special function
module.
(
(2) below)
(2) Countermeasures against the effects of quicker access to the special
function module
To use the AnS/A compatible special function module, adjust the execution time with
SM415 (2n-ms clock) and SD415 (2n-ms clock setting).
The initial value of SD415 is "30." When SD415 is used for interlock of the FROM/TO
instruction, the FROM/TO instruction is executed at every 120 ms.
POINT
To change the clock value of SM415, store the new value in SD415.
For details of SM415, refer to Appendix 1. For details of SD415, refer to Appendix
2.
Note2
Figure 8.9 Countermeasure program example
Basic
Process
Redundant
UD
Universal
Note8.1
Since the Basic model QCPU, Process CPU, Redundant CPU and Universal model QCPU do not
support the AnS/A series correponding special function modules, it is not necessary to be
conscious of the description in this section.
Basic
UD
Universal
Process
Redundant
SM415
FROMP H0
K1
K1
D0
