![Mitsubishi Electric melsec q00ucpu User Manual Download Page 84](http://html.mh-extra.com/html/mitsubishi-electric/melsec-q00ucpu/melsec-q00ucpu_user-manual_239147084.webp)
CHAPTER3 CPU MODULE OPERATION
1
2
3
4
5
6
7
8
3.2 I/O Ref
resh (Refr
esh Proc
essing with Input/Output Mo
dules)
3
-
2
3.2 I/O Refresh (Refresh Processing with Input/Output Modules)
The CPU module performs the following before sequence program operations.
• On/off data input from the input module or intelligent function module to the CPU module
• On/off data output from the CPU module to the output module or intelligent function module
When the constant scan time is set, I/O refresh is performed after the constant scan waiting time has
elapsed.
(I/O refresh is performed at each constant scan cycle.)
3.3 Program Operation
The CPU module sequentially executes the program stored in the module from the step 0 to the END or
FEND instruction.
3.4 END Processing
The CPU module performs refresh processing with network modules and communication with external
devices.
END processing includes the following.
• Refresh with network modules (
•
Auto refresh with intelligent function module
(
• Intelligent function module dedicated instruction processing (
• Device data latch processing (
• Service processing (
• Watchdog timer reset (
• Auto refresh between multiple CPU modules (
QCPU Userís Manual (Multiple CPU System))
• Device data collection using the sampling trace function (only when trace point is set to every scan (after
END instruction execution)) (
• Self-diagnostics processing (
• Special relay/special register value setting (only for those that should be set during END processing)
(
CHAPTER 12)
When the constant scan function (
Section 6.2) is used, the results of processing performed in
END processing are held for the period between after END processing is completed and until the
next scan starts.