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CHAPTER7 COMMUNICATIONS WITH INTELLIGENT FUNCTION MODULE
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7.2 Acce
ss to the AnS/A Se
ries Special Fun
ction Modules
7.2 Access to the AnS/A Series Special Function Modules
(1) Effect of high-speed access to the special function module
Processing time in the Q series CPU module has been speeded up so that the scan time is shortened.
If the FROM or TO instruction is frequently executed to a special function module in short scan, processing in the
special function module may not be completed correctly.
Note31
(2) Measures for high-speed access to the special function module
1) Adjust execution intervals of the FROM and TO instructions to the processing time and conversion time
using the timer and constant scan of the CPU module.
2) Adjust execution intervals of the FROM and TO instructions using SM415 (2n (ms) clock) or SD415 (2nms
clock setting).
If SM415 is used as an interlock for the FROM or TO instruction, the instruction is executed every 120ms
since the initial value of SD415 has been set to "30".
When changing the SM415 clock, store the changed value in SD415.
For details of SM415 and SD415, refer to the following.
QCPU User's Manual (Hardware Design, Maintenance and Inspection)
Note31
Figure 7.9 Program example
Note7.1
The Basic model QCPU, Process CPU, and Redundant CPU do not support the AnS/A series special function
modules.
Basic
Process
Redundant
SM415
FROMP H0
K1
K1
DO
