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6. DATA COMMUNICATIONS WITH SPECIAL FUNCTION MODULES
POINT
1. When reading data from the special function module frequently during the
programming, store the special direct device to a data register after reading in
an area of the program by using the FROM instruction rather than by using
them at each instruction.
This is because programming scan interval is added due to an access
processing to the special function module for each instruction.
2. When executing the instruction using a special direct device for the special
function module frequently in short scan time, it may cause the target special
function module operation error.
When performing the instruction using a special direct device, match the
processing time and conversion time of the special function module using
timer or constant scanning.
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