No parameters forwarded to M6 script?

[RS274NGC]
RS274NGC_STARTUP_CODE = F10 S300 G21 G17 G40 G49 G54 G64 P0.001 G80 G90 G91.1 G92.1 G94 G97 G98
REMAP = M6 modalgroup=6 ngc=toolchange
PARAMETER_FILE = linuxcnc.var
OWORD_NARGS = 1
NO_DOWNCASE_OWORD = 1
SUBROUTINE_PATH = subroutines

net tool-number              <= iocontrol.0.tool-prep-number
net tool-change-loop         iocontrol.0.tool-change => iocontrol.0.tool-changed
net tool-prep-loop           iocontrol.0.tool-prepare => iocontrol.0.tool-prepared

%
(MSG, --- Start of toolchange.ngc [Persistent Version] ---)

o<toolchange> sub

    ; ---------------------------------------------------------------
    ; DEBUG: Display raw numeric values passed by the M6 prolog.
    ; Typically, #100 is the requested tool and #120 is the selected pocket.
    ; ---------------------------------------------------------------
    (MSG, Debug: Received #100 = [#100], #120 = [#120])

    ; ---------------------------------------------------------------
    ; A) Reverse Assignment:
    ;    The M6 prolog passes numeric variables:
    ;      #100 = requested tool number,
    ;      #120 = selected pocket.
    ;    We use persistent variables for the current tool and pocket:
    ;      #3991 holds the current tool in the spindle.
    ;      #3990 holds the current tool pocket.
    ;    Now we set descriptive variables as follows:
    ; ---------------------------------------------------------------
    #<selected_tool>      = #100
    #<tool_in_spindle>    = #3991
    #<selected_pocket>    = #120
    #<current_pocket>     = #3990

    ; ---------------------------------------------------------------
    ; DEBUG: Display the descriptive variable values after assignment.
    ; ---------------------------------------------------------------
    (MSG, Debug: selected_tool = [#<selected_tool>])
    (MSG, Debug: tool_in_spindle = [#<tool_in_spindle>])
    (MSG, Debug: selected_pocket = [#<selected_pocket>])
    (MSG, Debug: current_pocket = [#<current_pocket>])

    ; ---------------------------------------------------------------
    ; B) Check if tool change is needed:
    ;    If the requested tool equals the tool already in the spindle,
    ;    no change is needed.
    ; ---------------------------------------------------------------
    o<if_same_tool> if [#<selected_tool> EQ #<tool_in_spindle>]
        (MSG, Tool [#<tool_in_spindle>] is already in spindle. No change needed.)
        M99
    o<if_same_tool> endif

    ; ---------------------------------------------------------------
    ; C) Stop the spindle (no M19 orientation used)
    ; ---------------------------------------------------------------
    M5

    ; ---------------------------------------------------------------
    ; D) Rack Coordinates & Z Heights (adjust as needed)
    ;    Define rack X, Y base, Y pitch.
    ;    Define Z heights if not already defined in the INI:
    ;       #<atc_z_tool_change_height> = -49.5
    ;       #<atc_z_tool_clearance_height> = 0
    ; ---------------------------------------------------------------
    #<rack_x>             = 1123
    #<rack_y_base>        = 164
    #<rack_y_pitch>       = 50
    #<atc_z_tool_change_height>    = -49.5   ; if not defined in INI
    #<atc_z_tool_clearance_height> = 0       ; if not defined in INI

    ; Move Z to clearance height.
    G53 G0 Z[#<atc_z_tool_clearance_height>]

    ; ---------------------------------------------------------------
    ; E) Drop Off Old Tool:
    ;    If a tool is currently in the spindle, drop it off in the current pocket.
    ; ---------------------------------------------------------------
    o<if_drop_old_tool> if [#<tool_in_spindle> GT 0]
        ; Calculate Y coordinate for the current pocket.
        #<old_pocket_y> = [#<rack_y_base> + ([#<current_pocket>] - 1) * #<rack_y_pitch>]
        G53 G0 X[#<rack_x>] Y[#<old_pocket_y>]
        G53 G0 Z[#<atc_z_tool_change_height>]
        (MSG, Unclamping old tool [#<tool_in_spindle>] with M64 P2)
        M64 P2
        G4 P1  ; dwell 1 second
        G53 G0 Z[#<atc_z_tool_clearance_height>]
        ; Optionally: update a pocket table (#4001..#4024) if needed.
    o<if_drop_old_tool> endif

    ; ---------------------------------------------------------------
    ; F) Pick Up New Tool:
    ;    Move to the selected pocket and clamp the new tool.
    ; ---------------------------------------------------------------
    o<if_pickup_new_tool> if [#<selected_tool> GT 0]
        ; Calculate Y coordinate for the selected pocket.
        #<new_pocket_y> = [#<rack_y_base> + ([#<selected_pocket>] - 1) * #<rack_y_pitch>]
        G53 G0 X[#<rack_x>] Y[#<new_pocket_y>]
        G53 G0 Z[#<atc_z_tool_change_height>]
        (MSG, Clamping new tool [#<selected_tool>] with M65 P2)
        M65 P2
        G4 P1  ; dwell 1 second
        G53 G0 Z[#<atc_z_tool_clearance_height>]
        ; Optionally: mark that pocket empty in your pocket table.
    o<if_pickup_new_tool> endif

    ; ---------------------------------------------------------------
    ; G) Update the Spindle:
    ;    Set the new tool as the one in the spindle.
    ; ---------------------------------------------------------------
    #<tool_in_spindle> = #<selected_tool>

    ; ---------------------------------------------------------------
    ; H) Inform LinuxCNC:
    ;    Set new tool active (M61) and load tool offset (G43).
    ; ---------------------------------------------------------------
    M61 Q[#<selected_tool>]
    G43 H[#<selected_tool>]

    ; ---------------------------------------------------------------
    ; I) Update Persistent Variables:
    ;    #3991 now holds the new tool.
    ;    #3990 is updated to the selected pocket.
    ; ---------------------------------------------------------------
    #3991 = #<selected_tool>
    #3990 = #<selected_pocket>

    (MSG, The spindle now has tool [#<selected_tool>])

    ; ---------------------------------------------------------------
    ; J) Return to caller.
    ; ---------------------------------------------------------------
    M99

o<toolchange> endsub

M2

(MSG, --- End of toolchange.ngc ---)
%

[PYTHON]
PATH_PREPEND = python
TOPLEVEL = python/toplevel.py