3.6. Python Scripts

3.6.1. Grbl G-code Feeder

The grbl_stream.py script is copied from the grbl firmware for Arduino CNC motion distribution for convenience.

3.6.2. Sample Code for G-code Generation

This script is used for {broken link}.

g_code_osc_fn.py : demonstration of creating an oscillatory motion represented as a G-code using a simple function

This is a fully self-contained script, i.e. it does not require any special libraries.

This emits a NC program with speeds faster than the grbl defaults. Please issue the following commands using a terminal emulator to set the non-volatile registers:

$110=2000 $120=500
Afterward, the $$ command should show these entries:
$110=2000.000 (x max rate, mm/min) $120=500.000 (x accel, mm/sec^2)
scripts.g_code_osc_fn.curve(time, frequency=0.2, magnitude=2.0)[source]

Return a single-axis position value representing a position on a curved path at a given time.

  • time – time in seconds
  • frequency – rate in cycles/second (Hz)

position in mm

scripts.g_code_osc_fn.emit_move(output, x_position, speed)[source]

Emit a single-axis move to the given location at the given speed. The precision is limited to three decimal places.

  • x_position – target position in mm
  • speed – motion rate in mm/min

Emit a header of G-code commands to reset the machine modes to a known standard state, including the following:

G21 units are mm G90 absolute distance mode G17 select XY plane for arcs G94 set units/mm feed rate mode G54 use default work coordinates

scripts.g_code_osc_fn.emit_rapid_move(output, x_position)[source]

Emit a single-axis rapid move to the given location at the maximum speed. The position precision is limited to three decimal places.

Parameters:x_position – target position in mm