Laser on Duet3d mini5+

Hi, I am trying to add a laser head to my cnc machine and cannot work out how to control it... The cnc is a home-built MPCNC with a 'Big Dipper' Duet3 mini5+ control board and RRF 3.4.4, the laser head is a Laser Tree 6W. PWM control is from io6 and I can turn the laser on or off fully by inverting the pin in firmware but I can't control it with G1 Sxx as I anticipated. Can anyone help please. Perhaps I am using the wrong Gcode? Here is my config.g file..:
; Configuration file for Duet 3 Mini 5+ (firmware version 3.3)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool v3.3.15 on Sat Nov 26 2022 15:03:43 GMT+0000 (Greenwich Mean Time)

; General preferences
M575 P1 S1 B57600 ; enable support for PanelDue
G90 ; send absolute coordinates...
M83 ; ...but relative extruder moves
M550 P"CNC - laser" ; set printer name
M918 P1 E4 F2000000 ; configure direct-connect display

; Network
M552 S1 ; enable network
M586 P0 S1 ; enable HTTP
M586 P1 S0 ; disable FTP
M586 P2 S0 ; disable Telnet

; Drives
M569 P0.0 S1 ; physical drive 0.0 'X1' goes forwards
M569 P0.1 S0 ; physical drive 0.1 'X2'goes backwards
M569 P0.2 S0 ; physical drive 0.2 'Y1' goes forwards
M569 P0.3 S1 ; physical drive 0.3 'Y2' goes backwards
M569 P0.4 S0 ; physical drive 0.4 'Z' goes forwards
M584 X0.0:0.1 Y0.2:0.3 Z0.4 ; set drive mapping
M350 X16 Y16 Z16 I1 ; configure microstepping with interpolation
M92 X100.00 Y100.00 Z2560.00 ; set steps per mm
M566 X500.00 Y500.00 Z300.00 ; set maximum instantaneous speed changes (mm/min)
M203 X3500.00 Y3500.00 Z700.00 ; set maximum speeds (mm/min)
M201 X300.00 Y300.00 Z250.00 ; set accelerations (mm/s^2)
M906 X800 Y800 Z800 I30 ; set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout

; Axis Limits
M208 X-650 Y-600 Z-250 S1 ; set axis minima
M208 X650 Y600 Z200 S0 ; set axis maxima

; Endstops
M574 X1 S1 P"io5.in+io1.in" ; configure switch-type (e.g. microswitch) endstop for low end on X via pin ^io0.in
M574 Y1 S1 P"io2.in+io3.in" ; configure switch-type (e.g. microswitch) endstop for low end on Y via pin ^io1.in
M574 Z2 S1 P"io4.in" ; configure switch-type (e.g. microswitch) endstop for high end on Z via pin ^io2.in

; Z-Probe
M558 P5 C"^temp0" H5 F7200 T144000 ; set Z probe type to switch and the dive height + speeds
M558 H30 ;*** Remove this line after delta calibration has been done and new delta parameters have been saved
G31 P500 X0 Y0 Z0.7 ; set Z probe trigger value, offset and trigger height
;M557 X-635:215 Y-585:195 S20 ; define mesh grid

; Heaters
M140 H-1 ; disable heated bed (overrides default heater mapping)

; Fans
;M950 F0 C"out3" Q500 ; create fan 0 on pin out3 and set its frequency
;M106 P0 S0 H-1 ; set fan 0 value. Thermostatic control is turned off

; Tools
M563 P0 S"cnc" F0 ; define tool 0
G10 P0 X0 Y0 Z0 ; set tool 0 axis offsets
G10 P0 R0 S0 ; set initial tool 0 active and standby temperatures to 0C
M563 P1 S"laser" D1 F0 ; define tool 1
G10 P1 X0 Y0 Z0 ; set tool 1 axis offsets
G10 P1 R0 S0 ; set initial tool 1 active and standby temperatures to 0C

; Custom settings are not defined

; Miscellaneous
T0 ; select first tool

; laser
M452 C"out6" R255 F1200 ; Enable Laser mode, on out6, with max intensity being 255, and a PWM frequency of 1200

Sorted now I think....