o<probe_x_minus> sub

#<feed_ruff> = #1        (feed rate from UI main screen DRO)
#<feed_fine> = [#<feed_ruff> / 20]

G92.1  (Cancel G92 offset, maybe some day it should be allowed)

o100 if [#<_metric> EQ 1]
    #<unit_conv> = 25.4
o100 else
    #<unit_conv> = 1
o100 endif

o110 if [#5220 EQ 1]     (G54, 5520 = current work space ID 1-9) 
  #<workspace_x> = #5221
o110 elseif [#5220 EQ 2] (G55)
  #<workspace_x> = #5241
o110 elseif [#5220 EQ 3] (G56)
  #<workspace_x> = #5261
o110 elseif [#5220 EQ 4] (G57)
  #<workspace_x> = #5281
o110 elseif [#5220 EQ 5] (G58)
  #<workspace_x> = #5301
o110 elseif [#5220 EQ 6] (G59)
  #<workspace_x> = #5321
o110 elseif [#5220 EQ 7] (G59.1)
  #<workspace_x> = #5341
o110 elseif [#5220 EQ 8] (G59.2)
  #<workspace_x> = #5361
o110 elseif [#5220 EQ 9] (G59.3)
  #<workspace_x> = #5381
o110 else                (default to G54)
  #<workspace_x> = #5221
o110 endif

#<x_min> = [[#<_ini[AXIS_0]MIN_LIMIT> - #<workspace_x> + .001] * #<unit_conv>]
#<x_start> = #5420       (Current X Position including offsets in current program units)

#<tip_radius> = [[#5410 / 2] * #<unit_conv>]  (Probe Tip Radius)
#<ruff_ret> = [.050 * #<unit_conv>]

(fast probe)
F #<feed_ruff>
G38.2 X #<x_min>
#<x_minus_ruff> = #5061

(partial retract)
G38.6 X [#<x_minus_ruff> + #<ruff_ret>]

(slow probe)
F #<feed_fine>
G38.2 X #<x_min>
o120 if [#5070]     (probing succesful)
  #<x_minus> = #5061
  M68 E 12 Q [#<x_minus> - #<tip_radius>]  (set analog output 12 to the x probed point - tip radius)
o120 else
  M68 E 12 Q 0.0
o120 endif

(retract to start)
F #<feed_ruff>
G38.6 X #<x_start>

o<probe_x_minus> endsub

M02 (end program)