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MITSUBISHI ELECTRIC 700 Series User Manual

Page 68

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63

Overview

3

SEQUENCE PRO

G

RAM

M

ING

Fig 3.1 Operation Processings of Built-in PLC function

Sequence program operation processing

Step 0

to

Until execution of END instruction

Power on

I/O refresh processing

Initial processing

I/O initialization
Data memory initialization
Self-diagnostic checks

END processing

Self-diagnostic checks
Updating of timer and counter present values
and on/off of their contacts