NC programs process their blocks in the sequence in which they were arranged when they were written. The processing sequence can be changed by introducing program jumps. The jump destination can be a block with a label or with a block number. This block must be located within the program.

Labels can be freely selected, but must follow some orders. Labels that are in the block that serves as the jump destination are ended by a colon. They must locate at the start of a block. If a block number is also present, the label is located after the block number.

Example:

Label1: G01 X20                                          ;Label1 is the label, jump destination

…

N100 GOTOB Label1    ;Jump to Label1 block

1.4.1 Unconditional program jumps

The unconditional jump instruction requires a separate block.

Example:

GOTOF Label     ; Jump forward (towards the last block of the program)

GOTOB Label     ; Jump backward (towards the first block of the program)

1.4.2 Conditional program jumps

Jump conditions are formulated after the IF instruction. If the jump condition (value not zero) is satisfied, the jump takes place. The jump destination can be a block with a label or with a block number. This block must be located within the program. Conditional jump instructions require a separate block.

Example:

IF condition GOTOF Label                           ; Jump forward

IF condition GOTOB Label                          ; Jump backward

Comparative operations:

= = Equal to

! = Not equal to

>  Greater than

<  Less than

> = Greater than or equal to

< = Less than or equal to

Example:

N10 IF R1>1 GOTOF Label      ; If R1 is greater than 1, go to the block with Label