O<tool-change> SUB

#<_UseInches> =           0     ( set to 1 to use inches here, or 0 to use millimeters; should match units on tool.tbl dimensions )
#<_TravelZ> =          0     ( machine Z coordinate for travelling, typically near max Z to avoid ever hitting the work )
#<_TravelFeed> =     3000     ( feedrate used for general Z moves when avoiding G0 )
#<_ProbeX> =          9.5     ( machine X coordinate of switch/touch-off plate )
#<_ProbeY> =            24.5     ( machine Y coordinate of switch/touch-off plate )
#<_ProbeFastZ> =        -20    ( machine Z coord to move to before starting probe, longest tool should not touch switch at this Z )
#<_ProbeMinZ> =       -70     ( machine Z coord to stop probe, shortest tool must touch switch at this Z, must be > min Z )
#<_ProbeRetract> =      0.5     ( small distance to retract before approaching switch/touch-off plate second time )
#<_ProbeFastFeed> =   3000     ( feed rate for moving to _ProbeFastZ )
#<_ProbeFeed1> =       750    ( feed rate for touching switch/touch-off plate first time )
#<_ProbeFeed2> =       3     ( feed rate for touching switch/touch-off plate second time )
#<_ToolChangeX> =       100     ( machine X coordinate to pause at for manual tool changing )
#<_ToolChangeY> =     100     ( machine Y coordinate to pause at for manual tool changing )
#<_MistOnDuringProbe> =   0     ( set to 1 for mist, or 2 for coolant, or 0 for nothing during probing, to clear switch of swarf )



O100 IF [ EXISTS[#<_ToolDidReferance>] EQ 0 ]
        #<_ToolDidReferance> = 0
O100 ENDIF

O101 IF [ EXISTS[#<_IgnoreFirstTool>] EQ 0 ]
        #<_IgnoreFirstTool> = 0
O101 endif

O102 IF [ #<_IgnoreFirstTool> EQ 0 ]
        #<_IgnoreFirstTool> = 1
O102 ELSE
    M49 (disable spindle speed and feed rate override controls)
    O105 IF [ #<_ToolDidReferance> EQ 0 ]
    G49                                         ( clear tool length compensation prior to saving state if this is first time )
    O105 ENDIF
(AXIS,hide)
    M6                                             ( do the normal M6 stuff )
    M70                                            ( save current modal state )

    M9                                             ( turn off coolant, will be restored on return if it was on )
    M5                                             ( turn off spindle, cannot be on during the probe )
    G[21 - #<_UseInches>]                          ( use inches or millimeters as required here, units will be restored on return )
    G30.1                                          ( save current position in #5181-#5183... )
    G49                                            ( clear tool length compensation )
    G90                                            ( use absolute positioning here )
    G94                                            ( use feedrate in units/min )
    G40                                            ( turn cutter radius compensation off here )

    G53 G1 F[#<_TravelFeed>] Z[#<_TravelZ>]      ( go to high travel level on Z )
    
    O200 IF [ #<_ToolDidReferance> EQ 0 ]
    G53 G0 X[#<_ProbeX>] Y[#<_ProbeY>]           ( to probe switch )
    G53 G1 F[#<_ProbeFastFeed>] Z[#<_ProbeFastZ>]( move tool closer to switch -- we shouldn't hit it )
    G54 G1 F[#<_ProbeFeed1>] G91                 ( use relative positioning )
    O103 IF [ #<_MistOnDuringProbe> EQ 1 OR #<_MistOnDuringProbe> EQ 2 ]
        M[7 + #<_MistOnDuringProbe> - 1]           ( turn on mist/coolant )
    O103 ENDIF
    G38.2 Z[#<_ProbeMinZ> - #<_ProbeFastZ>] F[#<_ProbeFeed1>]    ( trip switch slowly )
    G0 Z[#<_ProbeRetract>]                       ( go up slightly )
    G38.2 Z[#<_ProbeRetract>*-1.25] F[#<_ProbeFeed2>]   ( trip switch very slowly )
    M9                                           ( turn off mist )
    G90                                          ( use absolute positioning )
    #<_ToolZRef> = #5063                         ( save trip point )
    #<_ToolZLast> = #<_ToolZRef>                 ( save last tool Z position )
    G53 G1 F[#<_TravelFeed>] Z[#<_TravelZ>]      ( return to safe level )
    #<_ToolDidReferance> = 1                         ( we have been in this section to set reference value already )
    G53 G0 X[#<_ToolChangeX>] Y[#<_ToolChangeY>] ( nice place for changing tool )
    (MSG, SwitchTool )
    M0                                           ( pause execution )
    O200 ENDIF
    
    G53 G0 X[#<_ProbeX>] Y[#<_ProbeY>]           ( to high place directly over switch )
    G53 G1 F[#<_ProbeFastFeed>] Z[#<_ProbeFastZ>]( move tool closer to switch -- we shouldn't hit it )
    G54 G1 F[#<_ProbeFeed1>] G91                 ( use relative positioning )
    O104 IF [ #<_MistOnDuringProbe> EQ 1 OR #<_MistOnDuringProbe> EQ 2 ]
        M[7 + #<_MistOnDuringProbe> - 1]           ( turn on mist/coolant )
    O104 ENDIF
    G38.2 Z[#<_ProbeMinZ> - #<_ProbeFastZ>] F[#<_ProbeFeed1>]     ( trip switch slowly )
    G4 P0.1
    G0 Z[#<_ProbeRetract>]                       ( go up slightly )
    G38.2 Z[#<_ProbeRetract>*-1.25] F[#<_ProbeFeed2>]   ( trip switch very slowly )
    M9                                           ( turn off mist )
    G90                                          ( use absolute positioning )
    #<_ToolZ> = #5063                            ( save new tool length )
    G43.1 Z[#<_ToolZ> - #<_ToolZRef>]            ( set new tool length Z offset, we do this now to show operator even though it has to be set again after M72 )
    #<_ToolZLast> = #<_ToolZ>                    ( save last tool length )
	G53 G0 Z[#<_TravelZ>]      					 ( return to safe level )
	G53 G0 X[#5181] Y[#5182]					 ( return to saved position )
	G53 G0 Z[#5183]
	M72											 ( restore modal state )
	M3
	G43.1 Z[#<_ToolZ> - #<_ToolZRef>]            ( set new tool length Z offset )
    M48 (enable spindle speed and feed rate override controls)
    (AXIS,show)
O102 ENDIF

O<tool-change> ENDSUB
M2