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Changes to the status report for Grbl version 1.0c

Updates to grbl have changed status reporting in version 1.0c (used in the X-controller I believe). These changes affect the output from the “?” status command to grbl.

Information here is based on version 1.0c (edge fork).

The status report mask (grbl parameter $10) has two new control bits to select display of the probe pin and control pins’ status.

The bit assignments are as follows:

7 - Not used at this time
6 - display control pin status
5 - display probe pin status
4 - display homing/limit pin status
3 - display serial receive buffer usage
2 - display plannar block buffer usage
1 - display Work position
0 - display Machine position

When pin status is requested, the display format is Pin:000|0|0000 where the first set of values is for the homing/limit switches, the second value is for the probe pin, and the third value is for the control pins. The display only includes the values for the information requested in the status report mask.

A value of zero indicates that the pin function in question is not tripped and a value of one indicates that the pin function is tripped.

For, example: if you only set the bit (bit 4) for homing/limit switch status you will see Pin:000||

For the homing/limit switch status the order is Z axis, Y axis, X axis.

Example Pin:010|| would indicate that the homing/limit switch for the Y axis is tripped.

The probe value is a single use value and it indicates the state (tripped, not tripped) of the probe pin.

The order for the control pin status is:
cycle start, feed hold, reset, safety door

Example Pin:||010 would indicate that the feed hold pin is tripped.

Some configurations will not show the safety door state.

Most of the time these status values will only be used for machine setup or debugging a problem with the machine.

For performance reasons you would want to keep the number of active status items to a minimum which is why the default for the status report mask is 3 ($10=3) (Work position and Machine position).

Please be aware that Grbl v1.0c is not finalized and is subject to further change, which is highly likely.


Sure. That’s why I was clear to point out that I was referring to the edge fork.

But, thanks for making it clearer.