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Computing the Cycle Time Section 10-4
Calculation Example
10-4-5 Online Editing Cycle Time Extension
When online editing is executed from a Programming Device (such as Pro-
gramming Console or CX-Programmer) while the CPU Unit is operating in
MONITOR mode to change the program, the CPU Unit will momentarily sus-
pend operation while the program is being changed. The period of time that
the cycle time is extended is determined by the following conditions.
• Editing operations (insert/delete/overwrite).
• Types of instructions used.
The cycle time extension for online editing will be negligibly affected by the
size of task programs.
The following table shows the maximum expected cycle time extension due to
online editing when the maximum program size for each task is 64 Ksteps.
User program 20 Ksteps LD instructions: 12 Ksteps
MOV instructions: 6 Ksteps
+F instructions: 2K steps
Note:
• LD: Each instruction is 1 step.
• MOV: Each instruction is 3 steps.
• +F: Each instruction is 4 steps
Peripheral port connection Yes and no
Fixed cycle time processing No
RS-232C port connection No
Peripheral servicing with other
devices (Special I/O Units, CPU
Bus Units, and file access)
No
Item Details
Process name Calculation Processing time
With Programming
Device
Without Programming
Device
(1) Overseeing --- 0.13 ms 0.13 ms
(2) Program execution 0.016 µs × 12,000 + 0.14 µs/
3 steps × 6,000 + 0.24 µs/
4 steps × 2,000
0.59 ms 0.59 ms
(3) Cycle time calculation (Fixed cycle time not set) 0 ms 0 ms
(4) I/O refreshing 0.0041 ms × 2 + 0.0041 ms × 2
+ 0.05 ms × 2 + 0.19 ms × 2
0.4964 ms 0.4964 ms
(5) Peripheral servicing (Peripheral port connected only) 0.1 ms 0 ms
Cycle time (1) + (2) + (3) + (4) + (5) 1.3164 ms 1.2164 ms
CPU Unit Increase in cycle time for online editing
CJ1-H-R CPU Unit (CPU6@H-R) 8 ms
CPU6@H CJ1-H Unit (CPU6@)8 ms
CPU4@H CJ1-H Unit (CPU4@)11 ms
CJ1M CPU Unit 14 ms (Program size: 20 steps)
CJ1 CPU Unit 12 ms
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