Simple jobs do not complete

LaserWeb information

On the About page, I see that I have:

  • Frontend version: 4.0.996_________
  • Backend version: 4.0.136_________

My settings are:

  "settings": {
    "__version": "4.0.996",
    "__selectedProfile": "*gen_grbl",
    "__latestRelease": "2019-11-26T10:42:57Z",
    "showMachine": false,
    "machineWidth": 300,
    "machineHeight": 200,
    "machineBeamDiameter": 0.2,
    "machineBottomLeftX": 0,
    "machineBottomLeftY": 0,
    "machineFeedRange": {
      "XY": {"min": 1, "max": 50000},
      "Z": {"min": 1, "max": 50000},
      "A": {"min": 1, "max": 50000},
      "S": {"min": 0, "max": 30000}
    "machineXYProbeOffset": 0,
    "machineZEnabled": false,
    "machineZMatThickness": 0,
    "machineZToolOffset": 0,
    "machineZStartHeight": "",
    "machineZProbeOffset": 0,
    "machineAEnabled": false,
    "machineBlowerEnabled": false,
    "machineBlowerGcodeOn": "",
    "machineBlowerGcodeOff": "",
    "pxPerInch": 96,
    "forcePxPerInch": false,
    "dpiBitmap": 300,
    "toolGridWidth": 400,
    "toolGridHeight": 300,
    "toolGridMinorSpacing": 10,
    "toolGridMajorSpacing": 50,
    "toolSafetyLockDisabled": false,
    "toolCncMode": false,
    "toolImagePosition": "BL",
    "toolUseNumpad": false,
    "toolDisplayCache": false,
    "toolUseGamepad": false,
    "toolCreateEmptyOps": false,
    "toolVideoDevice": null,
    "toolVideoPerspective": {"enabled": false},
    "toolVideoLens": {"a": 1, "b": 1, "F": 1, "scale": 1},
    "toolVideoFov": {"x": 1, "y": 1},
    "toolVideoResolution": "720p(HD)",
    "toolVideoOMR": false,
    "toolVideoOMROffsetX": 0,
    "toolVideoOMROffsetY": 0,
    "toolVideoOMRMarkerSize": 20,
    "toolWebcamUrl": "",
    "toolFeedUnits": "mm/min",
    "toolTestSValue": 1,
    "toolTestDuration": 0,
    "gcodeStart": "G21         ; Set units to mm\r\nG90         ; Absolute positioning\r\nM4 S0       ; Enable Laser/Spindle (0 power)\r\n",
    "gcodeEnd": "M5          ; Disable Laser/Spindle\r\n",
    "gcodeHoming": "$H",
    "gcodeGenerator": "default",
    "gcodeToolOn": "",
    "gcodeToolOff": "",
    "gcodeLaserIntensity": "S",
    "gcodeLaserIntensitySeparateLine": false,
    "gcodeSMinValue": 0,
    "gcodeSMaxValue": 1000,
    "gcodeCheckSizePower": 0,
    "gcodeToolTestPower": 75,
    "gcodeToolTestDuration": 300,
    "gcodeConcurrency": 5,
    "gcodeCurvePrecision": 1,
    "comServerVersion": "4.0.136",
    "comServerIP": "",
    "comServerConnect": false,
    "comInterfaces": ["USB", "ESP8266", "Telnet"],
    "comPorts": [
        "manufacturer": "FTDI",
        "serialNumber": "D306OF5U",
        "pnpId": "usb-FTDI_FT230X_Basic_UART_D306OF5U-if00-port0",
        "vendorId": "0403",
        "productId": "6015",
        "comName": "/dev/ttyUSB0"
      {"comName": "/dev/ttyAMA0"}
    "comAccumulatedJobTime": 1485,
    "connectVia": "USB",
    "connectPort": "/dev/ttyUSB0",
    "connectBaud": "115200",
    "connectIP": "",
    "jogStepsize": 10,
    "jogFeedXY": 800,
    "jogFeedZ": 300,
    "macros": {
      "*GotoXY0": {
        "label": "Goto XY zero",
        "gcode": "G0 X0Y0",
        "keybinding": "ctrl+f1",
        "_locked": false
      "*LaserOff": {
        "label": "LASER OFF",
        "gcode": "M5",
        "keybinding": "ctrl+f2",
        "_locked": false
    "uiFcDrag": null
<go to Settings / Tools and save your LaserWeb Settings to a json file, 
then open that file with a text editor and copy/paste the content here>

Problem description

When I run a job, even a simple ellipse___, I expect it to complete_, but instead moves to the location, gets about halfway through an object and then it stops. The laser stays on until I abort and turn off laser. It will re-start another job without any problems but never finishes_ happens.

This problem is | has always happened.

## System description

* My machine is a | diode laser | 

* I have a tinyg


* I connect via USB to rPi running server and through websocket to MacOS running frontend

* My computer(s) on which I run LaserWeb run(s) <!-- choose all that apply -->  Mac version catalina

Here is my configuration:

<paste the contents of your machine configuration file or $$ output here>

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