here are my grbl settings
my unit is 500mm in the X and 1000mm in the Y
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$0=40 (step pulse, usec)
$1=4 (step idle delay, msec)
$2=64 (step port invert mask:01000000)
$3=3 (dir port invert mask:00000011)
$4=0 (step enable invert, bool)
$5=1 (limit pins invert, bool)
$6=0 (probe pin invert, bool)
$10=3 (status report mask:00000011)
$11=0,020 (junction deviation, mm)
$12=0,002 (arc tolerance, mm)
$13=0 (report inches, bool)
$20=1 (soft limits, bool)
$21=1 (hard limits, bool)
$22=1 (homing cycle, bool)
$23=3 (homing dir invert mask:00000011)
$24=25,000 (homing feed, mm/min)
$25=750,000 (homing seek, mm/min)
$26=250 (homing debounce, msec)
$27=1,000 (homing pull-off, mm)
$100=40,000 (x, step/mm)
$101=40,000 (y, step/mm)
$102=188,976 (z, step/mm)
$110=8000,000 (x max rate, mm/min)
$111=8000,000 (y max rate, mm/min)
$112=500,000 (z max rate, mm/min)
$120=500,000 (x accel, mm/sec^2)
$121=500,000 (y accel, mm/sec^2)
$122=50,000 (z accel, mm/sec^2)
$130=290,000 (x max travel, mm)
$131=750,000 (y max travel, mm)
$132=100,000 (z max travel, mm)
ok
ok