Hi,
I've installed the Duet3D wifi to my Ultimaker 2, and I am having trouble with the Z end stop. I issue the M119 command, and I get:

M119
Endstops - X: not stopped, Y: not stopped, Z: at max stop, Z probe: not stopped

So the board is detecting the stop. However, my Z motor continues to hum and my homez.g script never advances to the next line.

I have the Z stop switch at the bottom of my bed travel. I config the motors such that when I Machine Control (Z+10) the bed moves down. I am assuming when you mention lifting the head, it means to lower the bed.

Would you help me modify my config.g file to home the Z axis?

================= Here is my config.g: =============

; General preferences
M111 S0 ; Debugging off
G21 ; Work in millimetres
G90 ; Send absolute coordinates…
M83 ; ...but relative extruder moves
M555 P2 ; Set firmware compatibility to look like Marlin
M208 X0 Y0 Z0 S1 ; Set axis minima
M208 X215 Y215 Z200 S0 ; Set axis maxima

; Endstops
M574 X1 Y1 Z2 S0 ; Define active low and unused microswitches

; Drives
M569 P0 S0 ; Drive 0 goes backwards
M569 P1 S0 ; Drive 1 goes backwards
M569 P2 S0 ; Drive 2 goes forward
M569 P3 S1 ; Drive 3 goes forwards
M350 X16 Y16 Z16 E16 I1 ; Configure microstepping with interpolation
M92 X80 Y80 Z400 E80 ; Set steps per mm
M566 X900 Y900 Z500 E120 ; Set maximum instantaneous speed changes (mm/min)
M203 X6000 Y6000 Z1000 E1200 ; Set maximum speeds (mm/min)
M201 X500 Y500 Z350 E250 ; Set accelerations (mm/s^2)
M906 X800 Y800 Z800 E800 I30 ; Set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout

; Heaters
M143 S260 ; Set maximum heater temperature to 260C
M305 P0 X200 ; Set thermistor + ADC parameters for heater 0 and remap it to channel 100
M305 P1 X201 ; Set thermistor + ADC parameters for heater 1 and remap it to channel 101

; Tools
M563 P0 D0 H1 ; 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

============== Here is my homez.g: ==============
; Lift Z relatively to current position
G91
G1 Z5 F19000

; Back to absolute positioning
G90

; Go to first bed probe point and home the Z axis
G1 X15 Y15 F9000
G30

G91 ; relative mode
G1 Z200 F9000 S1 ; move Z down until the switch triggers

; Go back a few mm
G1 Z5 F9000
G90

; Move slowly to Z axis endstop once more (second pass)
G1 Z10 F360 S1

G90 ; back to absolute mode
G92 Z0.3 ; tell the firmware that we are at Z=0.3mm