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Discussion in 'Control Software' started by Sonny Jeon, Aug 12, 2015.

  1. David the swarfer

    David the swarfer OpenBuilds Team
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    follow the instructions at
    Compiling Grbl · gnea/grbl Wiki · GitHub
    for installing the latest GRBL on your controller.
    Use the 'via Arduino IDE' instructions so that you can use the Arduino IDE serial monitor (CTRL-SHIFT-M) to check that GRBL is happy. Set the serial speed to 115200 .
    after it connects you should see
    upload_2018-3-2_15-0-58.png
    which means that GRBL has booted ok.
    type $$ and press enter and it should display all the setup variables, further confirming it is ok.
     
  2. Crchisholm

    Crchisholm Well-Known
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    Is there something about the Z axis that requires special steps to make the end stops work on the grbl board. I have checked, double checked and rechecked the end stop connections, how they are plugged into the grbl, and the settings and they all seem ok (I have both min and max stops), but regardless, they don't want to work. min and max work on both the X and Y stops, but Z seems to ignore the stops. There is nothing different in how X, Y and Z are setup except the steps per mm. I wanted to test the homing, but if the Z stops are not recognized, I can't.

    Any suggestions?
     
  3. David the swarfer

    David the swarfer OpenBuilds Team
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    what version of GRBL?
    what compile options?
    what 'GRLB board'?

    and yes, there is something about the Z axis... in the transition from GRBL 0.8 to 0.9/1.1 the pins for Z limit and spindle PWM changed.... Connecting Grbl · grbl/grbl Wiki · GitHub
    but compile options can change it back if you don't need spindle PWM.

    knowledge is power! read the wiki! (-:
     
  4. Crchisholm

    Crchisholm Well-Known
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    David , the GRBL version is 0.9j
    The source is from the Arduino GRBL library and I did not specify any compiler options in the Arduino IDE.
    the board is from Amazon...
    https://www.amazon.com/gp/product/B06XSC52SL/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1
    No versioning or date on the board.

    The UNO that came with the board had a dead D8 pin, so I couldn't use it. The one I used instead is ...
    https://www.amazon.com/gp/product/B0168B39N4/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1
    I have bought a few of these boards and had good luck with them. I have a lagit UNO but didn't want to use it until I know everything else is good. (if at all)

    I could do without PWM if needed, but not sure how to go about "...but compile options can change it back "
     
  5. David the swarfer

    David the swarfer OpenBuilds Team
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    The clone boards have the CH340 usb chip on them which always has problems transmitting long streams of data, like when running a Gcode file (-:
    Swap to the legit Uno as soon as you can. (though the photo of the board in your second link appears to show a board with a 16u2 chip you have to check the board you have, around here the web photos seldom match what actually ships)
    All detailed in the GRBL Wiki that I linked to.

    Your board looks like the older ones which still expect the old pin numbering.
    Thus
    • Z+ limit is now the spindle PWM
    • SpnEn is now Z+ limit
     
  6. Crchisholm

    Crchisholm Well-Known
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    Yes, I read the wiki and I understand what changed between v0.8 and v0.9. My issue is ...
    • I can not find a CNC shield that looks like it might be v0.9 compatable
    • The buildlog.net stepper shield does not seem to be sold any more in the US because of a lead problem
    • I have the raspberry pi hat, but it looks different than the one in the wiki, so I really don't know if it is v0.9 compatable. Unfortunately I bought it from eBay which is where a lot of developers get rid of their sunset-ted versions.
    • You mentioned something about changing back with "compiler options" if I didn't and I an unclear on how to do that.
    Sorry for all the questions. There are just so many deminsions to this whole thing and I am tired of chasing my tail because of one stupid thing that I missed.
     
  7. Peter Van Der Walt

    Peter Van Der Walt OpenBuilds Team
    Staff Member Moderator Resident Builder Project Maker Contest Winner! Builder

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    (; don't support the knockoff/fake support channels: The original designer of that shield, Protoneer, has updated his product years ago: Arduino CNC Shield – 100% GRBL Compatable - see version 3.1 upwards. Of course the chinese fakes couldn't care less - they keep producing the old version because people keep buying it. Do the right thing and buy one from the original designer: not only doing the right thing, but also entitling you to support directly from the man who made it :)
     
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  8. Peter Van Der Walt

    Peter Van Der Walt OpenBuilds Team
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    Or just get an CNC xPRO V3 Controller Stepper Driver - drivers, connections, and GRBL all onboard ready to go. Learning curves can be frustrating - unless your time is worth $0 - are you really saving?
     
  9. Crchisholm

    Crchisholm Well-Known
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    Not a social security friendly product.
     
  10. Glenn67

    Glenn67 Well-Known
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    If I have posted this in the wrong spot please forgive me but I am not sure where to start.I'm having some trouble with my machine. I just finished it and have only run a few codes they were was successful until now. I am using an xProv2 controller and G code sender. I generated the codes in Fusion 360. I have set machine zero and than set work zero. I have set X zero Y zero on my work piece as the lower corner. The first operation is a center pocket hole ( centered in the work piece-10"x10" ). The bit starts at work piece zero zero, moves to machine zero while lowering the bit, than moves back toward the work piece but doesn't raise the spindle and will crash into the piece if I let it. I tried it without the wood in place and it raises the spindle when it gets to the center of the piece. I am almost certain I am doing something wrong but I cut this operation before and I haven't made any changes to the file. Long winded I know but any help is appreciated.
    Glenn
     
  11. David the swarfer

    David the swarfer OpenBuilds Team
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    The problem is in your Machine Coordinate System (also known as home) and your G28 settings.
    The controller uses several offset coordinate systems but they are all relative to machine coordinates.
    (Machine Position in UGS)
    The industry standard for machine co-ordinates is X at the positive end, Y at the positive end, and Z at the positive end (all the way UP away from the work, a safe place!).
    When GRBL turns on it sets the machine cordinates to 0,0,0, this means that you have to physically position the machine before turning on.

    G28 normally defaults to 0,0,0 which means that it is the same as the machine co-ordinates.
    A G28.1 command will set the offsets to wherever the machine is at the time. Thus machine 0,0,0 can be anywhere IF you are willing to always move the machine to a safe place (Z high!) and issue G28.1

    When you set your workpeice coordinates you are changing one of the 6 Work Coordinate Systems, selected by G54 to G59. (note that UGS only ever sets G54 offsets, which is why I prefer bCNC vlachoudis/bCNC)
    (Work Position in UGS)

    Basically, Machine Position for Z will always be negative when zeroed to your work.

    The default Fusion360 postprocessor expects that the machine is set up according to industry standards and the machine coordinates and G28 are correctly set.

    You can turn off the initial G28 in the post settings
    OR
    you can use this post
    swarfer/GRBL-Post-Processor
    which does not use G28. It still expects that machine 0,0,0 is set correctly for safe movement at machine Z=0
     
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  12. Mark Carew

    Mark Carew OpenBuilds Team
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    This would make a great software resource David ;) Nice work man thank you for sharing this.
     
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  13. Maikaefer

    Maikaefer New
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    Hi,

    is there a possibility to use GRBL in some kind of non-CNC-mode?

    What I want to do is to control all axes but they should move independent from each other. Means I want to send a motion command to one axis, while it moves I send a motion command to a second axis. Now both axes operate in parallel but independent from each other, means each axis tries to reach its target position but they do not "draw" a 2D line.

    So what I want to do is to operate it more like a stepper motor controller and less like a 2D/3D CNC controller

    Thanks!
     
  14. David the swarfer

    David the swarfer OpenBuilds Team
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    no, grbl will not do that. Gcode is all about co-ordinated movement.

    but, you can use multiple arduinos running GRBL, each one driving one axis.
    now you can give each controller a separate command to do what you want.
     
  15. Ed Zacly

    Ed Zacly Well-Known
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    Greetings,

    I hope someone can answer this question...

    I have been in the process of setting up GRBL on my OX-Metal CNC router I have been systematically working my way through all of the control functions so that I could start to run my test patterns to calibrate..


    Issue: $20 - Soft limits, boolean

    As per the log below - After I initiate $21 Soft limits it doesn't allow me to enter any values in the Machine Control Tab on the universal G-Code sender that will allow me to move any of the three axis’s VIA the machine control tab .see log below as it sumarrizes all events...

    Can somebody tell me where the conflict is.. ? I'm thinking that there is something in the default settings that is conflicting with my
    Initiating the hard limit setting...

    Thanks & Regards, Ed Zac

    GRBL Log

    >>> $$
    $0=10
    $1=255
    $2=1
    $3=6
    $4=1
    $5=0
    $6=0
    $10=1
    $11=0.020
    $12=0.002
    $13=0
    $20=0
    $21=1
    $22=1
    $23=3
    $24=25.000
    $25=500.000
    $26=250
    $27=1.000
    $30=1000
    $31=0
    $32=0
    $100=197.938
    $101=200.200
    $102=199.400
    $110=2500.000
    $111=2500.000
    $112=2500.000
    $120=50.000
    $121=50.000
    $122=50.000
    $130=795.000
    $131=1200.000
    $132=69.000
    ok
    >>> G91 G0 X1
    ok
    >>> G91 G0 X-1
    ok
    >>> G91 G0 Y1
    ok
    >>> G91 G0 Y-1
    ok
    >>> $20=1
    ok
    Grbl 1.1f ['$' for help]
    [MSG:Check Limits]
    [MSG:'$H'|'$X' to unlock]
    >>> $X
    [MSG:Caution: Unlocked]
    ok
    >>> G91 G0 X1
    ALARM:2
    [MSG:Reset to continue]
    ok
    Grbl 1.1f ['$' for help]
    [MSG:Check Limits]
    [MSG:'$H'|'$X' to unlock]
    >>> $X
    [MSG:Caution: Unlocked]
    ok
    >>> $$

    $0=10
    $1=255
    $2=1
    $3=6
    $4=1
    $5=0
    $6=0
    $10=1
    $11=0.020
    $12=0.002
    $13=0
    $20=1
    $21=1
    $22=1
    $23=3
    $24=25.000
    $25=500.000
    $26=250
    $27=1.000
    $30=1000
    $31=0
    $32=0
    $100=197.938
    $101=200.200
    $102=199.400
    $110=2500.000
    $111=2500.000
    $112=2500.000
    $120=50.000
    $121=50.000
    $122=50.000
    $130=795.000
    $131=1200.000
    $132=69.000

    ok
     

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