View source for Touch Probe

http://www.craftycnc.com/touch-probes/

http://www.ebay.com/itm/171912530881

http://meshlab.sourceforge.net/

http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Touch_Probe

http://www.timeguy.com/cradek/01262579508

http://lab.whitequark.org/notes/2014-07-06/g38-probing-workpieces-in-linuxcnc/

http://www.scorchworks.com/Blog/auto-probing-with-g-code-ripper/

http://www.scorchworks.com/Gcoderipper/gcoderipper.html

LinuxCNC is distributed with gridprobe.ngc and smartprobe.ngc

<code>
( Rectangular Probing                                                   )
(                                                                       )
( This program repeatedly probes in a regular XY grid and writes the    )
( probed location to the file 'probe-results.txt' in the same directory )
( as the .ini file                                                      )

(Configuration section)
G20   (Inches)
F4    (probe speed)

#1=0  (X start)
#2=.25 (X increment)
#3=13 (X count)

#4=0
#5=.25
#6=5 (Y count)

#7=.1 (Z safety)
#8=-.5 (Z probe)
(End configuration section)

(PROBEOPEN probe-results.txt)
#9=0 #10=0
G0Z#7
O1 while [#9 lt #6]
    #10=0
    G0 Y[#4+#5*#9]
    O2 while [#10 lt #3]
        O3 if [[#9/2] - fix[#9/2] eq 0]
            G0X[#1+#2*#10]
        O3 else      
            G0X[#1+#2*[#3-#10-1]]
        O3 endif
        G38.2Z#8
        G0Z#7
        #10=[#10+1]
    O2 endwhile
    #9=[#9+1]
O1 endwhile

(PROBECLOSE)
G0Z#7
G0X#1Y#4
M2
</code>