Mitsubishi Electronics FX3G User Manual

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/FX

3GC

/FX

3UC

Series

Programming Manual - Basic & Applied Instruction Edition

8 Program Flow – FNC 00 to FNC 09

8.1 FNC 00 – CJ / Conditional Jump

Cautions

1. Relationship between the label input position and the list program

The figure below shows programming of a label.
When creating a circuit program, move the cursor to the left side of the bus line in the ladder diagram, and input a label
(P) at the head of the circuit block.

2. Programming a label in a smaller number step than CJ instruction

A label can be programmed in a smaller number step than CJ instruction. However, note that a watchdog timer error
occurs when the scan time exceeds 200 ms (default setting).

3. Jumping to one label from two or more CJ instructions

When the pointer number in operands is same and there is one label, the following operation is caused:
When X020 turns ON, the program execution jumps from CJ instruction corresponding to X020 to the label P9. When
X020 turns OFF and X021 turns ON, the program execution jumps from CJ instruction corresponding to X021 to the
label P9.

4. Using a label (P) two or more times

When a label number (including labels for CALL instructions described later) is used two or more times, an error is
caused.

X030

Label

P 20

X031

X032

Y011

Y010

FNC 00

P 20

X030

P 20

X031

OUT Y010

P 20

X032

OUT Y011

Pointer

Label

Bus
line

Label

P 10

X022

FNC 00

P 10

X020

X021

Label

P 9

FNC 00

P 9

FNC 00

P 9

Label

FNC 00

P 9

END

User program

X030

X020

P 9

FNC 00

P 9

Label

User program

Good

Bad