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Probing function (clear remaining distance)

G-Code: G31 / Any movement command together with the PROBE word

Function: The probing function (clear remaining distance) is a special movement which is aborted as soon as a signal (PROBE) is pending. The rest of the G-code continues from the position where the movement was aborted, not from the programmed end position of the movement.

The the probing function (clear remaining distance) causes an implicit decoding stop before the next movement (similar to G75). Decoding of the G-code will continue only after the signal has been received. Typical use cases include measuring a tool length (moving into a switch) or moving onto a block.

The probing function (clear remaining distance) can be activated for any number of movements, such as straight lines and circular arcs. For this, only the PROBE word has to be added to the G-code.

G31 is a linear movement with the probing function (clear remaining distance), with the default probe number 1. This default can be overridden with a PROBE word.

Note

  • Each movement may have at most one PROBE word.

  • H-functions (triggers) are not supported for movements with the probing function (clear remaining distance).

  • Path preprocessing such as corner smoothing, tool radius correction, etc. is not supported for movements with the probing function (clear remaining distance).

  • The probe number must be positive.

  • If no probe signal is received during the processing of a movement with the probing function (clear remaining distance), then the interpolation stops at the end of the movement with an error.

  • The interpolator first needs to be stopped when a probe signal is received. One of the inputs bSlow_Stop, bQuick_Stop, or bEmergency_Stop can be used for this purpose. As soon as the interpolation has stopped, the probing function (clear remaining distance) can be acknowledged. For this purpose, a rising edge is applied to the SMC_Interpolator.bAcknProbe input.

Syntax

G31 X Y Z A B C P Q U V W F E S PROBE
G1/2/3/8/9 X Y Z A B C P Q U V W F E S PROBE

G-Code Word

Description

X Y Z

Target positions of the Cartesian axes

A B C P Q U V W

Target positions of the additional axes

F E

Path velocity, path acceleration/deceleration

S

S profile

PROBE

The probe number must be positive.

Example 48. Examples

Linear movement

Linear motion with the probing function (clear remaining distance) and default probe number 1

N010 G31 X100

Circular movement

Circular movement with the probing function (clear remaining distance) and probe number 7

N010 G02 X100 R50 PROBE 7

For more information, see the example: CNC Example 16: Probing function (clear remaining distance) (G31)



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