M3 Stll Not Work

[cdb0ewm]

I accidentally download a program to the UNO so I had no response so I followed the directions to download the Gbrl program and it seemed to work but when I tried to move the Z Axis, it kept falling whenever I raised it. I had other issues with X and Y movements. So i started over and uploaded the Gbrl sketch.

When I opened the Universal G Code Sender it started scrolling the startup command continuously.

Just to check and see if the UNO might be the problem, I repeated the Gbrl procedure on a new UNO outside the M3 and when I opened the UGCSender it scrolled through the startup commands and stopped.

My thoughts are the existing UNO is fried but before I take it apart it would be great to hear from someone with more experience than me.

Thanks

[cdb0ewm]

After not getting any feedback I went ahead and changed the UNO. Same problem. I'm lost

[Bruce]

Check the default the GRBL settings, type $$ in the console. 

M3 GRBL Factory Settings:

$0=10 (step pulse, usec)
$1=255 (step idle delay, msec)
$2=0 (step port invert mask:00000000)
$3=0 (dir port invert mask:00000000)
$4=0 (step enable invert, bool)
$5=0 (limit pins invert, bool)
$6=0 (probe pin invert, bool)
$10=3 (status report mask:00000011)
$11=0.010 (junction deviation, mm)
$12=0.002 (arc tolerance, mm)
$13=0 (report inches, bool)
$20=0 (soft limits, bool)
$21=0 (hard limits, bool)
$22=1 (homing cycle, bool)
$23=0 (homing dir invert mask:00000000)
$24=25.000 (homing feed, mm/min)
$25=600.000 (homing seek, mm/min)
$26=244 (homing debounce, msec)
$27=4.000 (homing pull-off, mm)
$30 = 12000 (Maximum spindle speed, RPM)
$31 = 0 (Minimum spindle speed, RPM)
$32 = 0 (Laser-mode enable, boolean)

$100=40.000 (x, step/mm)
$101=40.000 (y, step/mm)
$102=80.000 (z, step/mm)
$110=8000.000 (x max rate, mm/min)
$111=8000.000 (y max rate, mm/min)
$112=3000.000 (z max rate, mm/min)
$120=250.000 (x accel, mm/sec^2)
$121=250.000 (y accel, mm/sec^2)
$122=250.000 (z accel, mm/sec^2)
$130=264.000 (x max travel, mm)
$131=264.000 (y max travel, mm)
$132=69.000 (z max travel, mm)

[cdb0ewm]

I compared my settings with these and made the changes except for 30, 31 and 32 which gave me errors. The z axis moves up and doesn't drop but when I tried a project that I have run before, the Z axis dropped down completely. Just to make sure I tried another old project and had the same results

[Bruce]

So when you try to home the Z axis it goes down instead of going up and hitting the limit switch? Have you checked the wiring connection of the Z motor to the CNC Shield?