===== GCode =====

  * https://www.shapeoko.com/wiki/index.php/G-Code
  * http://www.ofitselfso.com/LineGrinder/LineGrinder.php
  * http://www.re-innovation.co.uk/web12/index.php/en/blog-75/224-making-pcbs-with-linegrinder
  * http://flatcam.org/manual/procedures.html#isolation-routing
  * [[https://www.shapeoko.com/wiki/index.php/Touch_Plate|Touch_Plate]]
  * [[http://buildlog.net/cnc_laser/cnc/gcode_comment.html|GCode Commenter]]
  * http://linuxcnc.org/docs/2.6/html/gcode/gcode.html
  * http://reprap.org/wiki/G-code#G38.x_Straight_Probe_.28CNC_specific.29
  * http://www.custompartnet.com/calculator/drilling-speed-and-feed

<code>
G10 L20 P1 X0 Y0 Z0 // set wpos to zero
G38.2 Z-26 F100     // probe, copper height 4.25mm
G38.2 Z-26 F100;G91 G0 Z1

G38.2 Z-26 F100;G10 P0 L20 Z0;G91 G0 Z1 //probe and reset Z
</code>

==== Pre Job ====

<code>
$21=0
G38.2 Z-26 F100
G10 P0 L20 Z0
</code>
==== GCode Sender Commands ====


<code>
G91 X0 Y0;

//probe
G38.2 Z-26 F100;G10 P0 L20 Z0;G91 G0 Z1

//double probe
G38.2 Z-26 F100;G91 G0 Z1;G38.2 Z-26 F10;G10 P0 L20 Z0;G91 G0 Z1

M03 S10000;G01 Z-1.1
F100;G01 X10;G01 Y-0.265;G01 X-10;G01 Z1;M5
</code>

==== Post Job ====

<code>
$21=1
</code>

===== GRBL =====

  * https://github.com/grbl/grbl/wiki/Configuring-Grbl-v0.9
  * https://github.com/gnea/grbl/wiki
  * https://github.com/gnea/grbl/wiki/Setup-the-Homing-Cycle