* [https://github.com/fra589/grbl-Mega-5X/blob/edge/doc/markdown/settings.md grbl settings]
* [[File:GRBL Settings Pocket Guide Rev B.pdf|thumb]]
 $0=10 - Step Pulse Length (µsec)
 $1=254 - Step Idle Delay (msec)
 $2=0 - Step Pulse Configuration
 $3=0 - Axis Direction
 $4=0 - Step Enable Invert
 $5=0 - Limit Pins Invert
 $6=0 - Probe Pin Invert
 $10=1 - Status Report
 $11=0.020 - Junction Deviation (mm)
 $12=0.002 - Arc Tolerance (mm)
 $13=0 - Feedback Units
 $20=1 - Soft Limits (Enable/Disable)
 $21=0 - Hard Limits (Enable/Disable)
 $22=1 - Homing Cycle (Enable/Disable)
 $23=0 - Homing Cycle Direction
 $24=100.000 - Homing Feed (mm/min)
 $25=500.000 - Homing Seek (mm/min)
 $26=250 - Homing Debounce (msec)
 $27=5.000 - Homing Pull-off (mm)
 $30=12000 - Max spindle speed (RPM)
 $31=550 - Min spindle speed (RPM)
 $32=0 - Laser mode (boolean)
 $100=400.000 - X (steps/mm)
 $101=400.000 - Y (steps/mm)
 $102=400.000 - Z (steps/mm)
 $103=8.889 - [A] (steps/degre)
 $104=8.889 - [B] (steps/degre)
 $110=750.000 - X-Max Rate (mm/min)
 $111=750.000 - Y-Max Rate (mm/min)
 $112=750.000 - Z-Max Rate (mm/min)
 $113=1440.000 -  [A] Max rate (degre/min)
 $114=1440.000 -  [B] Max rate (degre/min)
 $120=50.000 - X-Max Acceleration (mm/sec<sup>2</sup>)
 $121=50.000 - Y-Max Acceleration (mm/sec<sup>2</sup>)
 $122=50.000 - Z-Max Acceleration (mm/sec<sup>2</sup>)
 $123=50.000 - [A] Acceleration (degre/sec<sup>2</sup>)
 $124=50.000 - [B] Acceleration (degre/sec<sup>2</sup>)
 $130=400.000 - X-Max Travel (mm)
 $131=200.000 - Y-Max Travel (mm)
 $132=200.000 - Z-Max Travel (mm)
 $133=360.000 - [A] Max travel (degres)
 $134=180.000 - [B] Max travel (degres)

==inversion table for machines with mirrored axes==
The settings page lists only inversion values for XYZ axes, however when using dual X or Y axis, inverting both motors requires inverting a currently undocumented (As far as I can find) N axis.

{| class="wikitable"
|-
!$3 Value	!! Mask	!! Invert X	!! Invert Y	!! Invert Z	!! Invert N
|-
| 0 ||	0000	|| N	|| N	|| N	|| N
|-
| 1 ||	0001	|| Y	|| N	|| N	|| N
|-
| 2 ||	0010	|| N	|| Y	|| N	|| N
|-
| 3 ||	0011	|| Y	|| Y	|| N	|| N
|-
| 4 ||	0100	|| N	|| N	|| Y	|| N
|-
| 5 ||	0101	|| Y	|| N	|| Y	|| N
|-
| 6 ||	0110	|| N	|| Y	|| Y	|| N
|-
| 7 ||	0111	|| Y	|| Y	|| Y	|| N
|-
| 8 ||	1000	|| N	|| N	|| N	|| Y
|-
| 9 ||	1001	|| Y	|| N	|| N	|| Y
|-
| 10 ||	1010	|| N	|| Y	|| N	|| Y
|-
| 11 ||	1011	|| Y	|| Y	|| N	|| Y
|-
| 12 ||	1100	|| N	|| N	|| Y	|| Y
|-
| 13 ||	1101	|| Y	|| N	|| Y	|| Y
|-
| 14 ||	1110	|| N	|| Y	|| Y	|| Y
|-
| 15 ||	1111	|| Y	|| Y	|| Y	|| Y
|}