CHAPTER3 CPU MODULE OPERATION
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3.8 I/O Processing and Response Delay
3.8.2 Direct mode
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3.8.2 Direct mode
(1) Definition
The direct mode is a mode for the CPU module to access input/output modules and performs I/O
processing at the timing when each instruction is executed in a sequence program.
With this mode, the CPU module uses the direct access input (DX) and direct access output (DY) to
perform I/O processing.
Figure 3.6 Direct mode
Input module or
output module
CPU module
Device memory
0
DX10
On/off
data
On/off data
Input of on/off data upon
instruction execution
Output of on/off data upon
instruction execution