Package: grbl-streamer
GrblStreamerUniversal interface module for thegrblCNC firmware, implemented as a Python 3 class.
It provides a convenient high-level API for scripting or integration into parent applications (e.g. GUIs).There are a number of streaming applications available for the grbl CNC controller, but none of them seem to be an universal, re-usable standard Python module. GrblStreamer attempts to fill that gap.FeaturesRe-usable moduleCallback basedgrbl's machine position updatesgrbl's probe events (PRB)grbl's alarm events (ALARM)grbl's errorsgrbl's bootinggrbl's settings updatesgrbl's g-code parser state updateslog lineskeeps a copy of grbl's state for immediate inspectionNon-blocking streaming of g-codeTwo streaming modes:Incrementalfast (keep grbl's receive buffer as full as possible by keeping track of submitted characters)Streaming from files or Python listsKeeps track of the fill percentage of grbl's receive bufferRequesting of grbl's settingsRequesting of grbl's parser state ('G' modes)Dry run (simulator) modeg-code buffer stashingpausing and resuming of the g-code streamcontrolled shutdownThe following features are also available, coming from my librarygcode-machine:G-Code compression by cleaning it upG-Code variable expansionDynamic feed overrideDynamic spindle overrideIntegration exampleSee GrblStreamer integrated with its full feature set in a graphical user interface based on Python 3 with Qt5 bindings:https://github.com/michaelfranzl/gerbil_gui.Installationpipinstallgrbl-streamerDocumentationThe module is only about 1300 lines of code, which is extensively documented.Getting startedfromgrbl_streamerimportGrblStreamerDefine a callback function that GrblStreamer will call asynchronously whenever some event happens.
The following example function does nothing else than logging to standard output.
In a real GUI application, you would update numbers, sliders etc. from this method.defmy_callback(eventstring,*data):args=[]fordindata:args.append(str(d))print("MY CALLBACK: event={}data={}".format(eventstring.ljust(30),", ".join(args)))Here, for just one example, is what above functionmy_callbackwill print out at this point:Instantiate the GrblStreamer class:grbl=GrblStreamer(my_callback)grbl.setup_logging()We now can connect to the grbl firmware, the actual CNC machine (adapt path and baudrate):grbl.cnect("/dev/ttyUSB0",115200)This will emit the eventson_boot,on_settings_downloadedand others.We will poll every half second for the state of the CNC machine (working position, etc.):grbl.poll_start()Now, we'll send our first G-Code command.
This will emit events likeon_movement,on_stateupdate,on_standstilland others.grbl.send_immediately("G1 X5 F50")Now let's send the$#command to the firmware, so that it reports back coordinate system offset information. The eventon_hash_stateupdatewill be emitted:grbl.hash_state_requested=TrueExample result:MY CALLBACK: event=on_hash_stateupdate            data={'G54': (0.0, 0.0, 0.0), 'G55': (0.0, 0.0, 0.0), 'G56': (0.0, 0.0, 0.0), 'G57': (0.0, 0.0, 0.0), 'G58': (0.0, 0.0, 0.0), 'G59': (0.0, 0.0, 0.0), 'G28': (0.0, 0.0, 0.0), 'G30': (0.0, 0.0, 0.0), 'G92': (0.0, 0.0, 0.0), 'TLO': (0.0,), 'PRB': (0.0, 0.0, 0.0)}Next, let's request the firmware G-code parser state (grbl's$Gcommand):grbl.gcode_parser_state_requested=TrueExample result:MY CALLBACK: event=on_gcode_parser_stateupdate    data=['1', '54', '17', '21', '90', '94', '0', '5', '9', '0', '50.', '0.']We also can request the settings (grbl's$$command), the result will be a dict:grbl.request_settings()GrblStreamer supports dynamic feed override. You could have a slider in your GUI controlling the milling speed of your machine as it runs:grbl.set_feed_override(True)grbl.request_feed(800)grbl.stream("F100 G1 X210\nG1 X200\nG1 Y210\nG1 Y200\n")When we're done, we disconnect from the firmware:grbl.disconnect()TestingOne log file says more than a thousand words. The following is a printout of runningpipenv run make testagainst a real microcontroller with grbl 0.9j:on_settings_downloaded: ({130: {'val': '1000', 'cmt': 'width'}, 131: {'val': '1000', 'cmt': 'height'}},)
           on_hash_stateupdate: ({'G54': (0, 0, 0), 'G55': (0, 0, 0), 'G56': (0, 0, 0), 'G57': (0, 0, 0), 'G58': (0, 0, 0), 'G59': (0, 0, 0), 'G28': (0, 0, 0), 'G30': (0, 0, 0), 'G92': (0, 0, 0), 'TLO': 0, 'PRB': (0, 0, 0)},)
   on_gcode_parser_stateupdate: (['0', '54', '17', '21', '90', '94', '0', '0', '5', '0', '99', '0'],)
                        on_log: mygrbl: Setting up interface on /dev/ttyUSB0
                        on_log: iface_mygrbl: connecting to /dev/ttyUSB0 with baudrate 115200
                       on_read: ("Grbl 0.9j ['$' for help]",)
              on_job_completed: ()
                on_feed_change: (None,)
           on_progress_percent: (0,)
          on_rx_buffer_percent: (0,)
                        on_log: mygrbl: Grbl has booted!
                       on_boot: ()
                      on_write: ('$$\n',)
                       on_read: ('$0=10 (step pulse, usec)',)
                       on_read: ('$1=25 (step idle delay, msec)',)
                       on_read: ('$2=0 (step port invert mask:00000000)',)
                       on_read: ('$3=0 (dir port invert mask:00000000)',)
                       on_read: ('$4=0 (step enable invert, bool)',)
                       on_read: ('$5=0 (limit pins invert, bool)',)
                       on_read: ('$6=0 (probe pin invert, bool)',)
                       on_read: ('$10=3 (status report mask:00000011)',)
                       on_read: ('$11=0.010 (junction deviation, mm)',)
                       on_read: ('$12=0.002 (arc tolerance, mm)',)
                       on_read: ('$13=0 (report inches, bool)',)
                       on_read: ('$20=0 (soft limits, bool)',)
                       on_read: ('$21=0 (hard limits, bool)',)
                       on_read: ('$22=0 (homing cycle, bool)',)
                       on_read: ('$23=0 (homing dir invert mask:00000000)',)
                       on_read: ('$24=25.000 (homing feed, mm/min)',)
                       on_read: ('$25=500.000 (homing seek, mm/min)',)
                       on_read: ('$26=250 (homing debounce, msec)',)
                       on_read: ('$27=1.000 (homing pull-off, mm)',)
                       on_read: ('$100=250.000 (x, step/mm)',)
                       on_read: ('$101=250.000 (y, step/mm)',)
                       on_read: ('$102=250.000 (z, step/mm)',)
                       on_read: ('$110=500.000 (x max rate, mm/min)',)
                       on_read: ('$111=500.000 (y max rate, mm/min)',)
                       on_read: ('$112=500.000 (z max rate, mm/min)',)
                       on_read: ('$120=10.000 (x accel, mm/sec^2)',)
                       on_read: ('$121=10.000 (y accel, mm/sec^2)',)
                       on_read: ('$122=10.000 (z accel, mm/sec^2)',)
                       on_read: ('$130=200.000 (x max travel, mm)',)
                       on_read: ('$131=200.000 (y max travel, mm)',)
                       on_read: ('$132=200.000 (z max travel, mm)',)
        on_settings_downloaded: ({130: {'val': '200.000', 'cmt': 'x max travel, mm'}, 131: {'val': '200.000', 'cmt': 'y max travel, mm'}, 0: {'val': '10', 'cmt': 'step pulse, usec'}, 1: {'val': '25', 'cmt': 'step idle delay, msec'}, 2: {'val': '0', 'cmt': 'step port invert mask:00000000'}, 3: {'val': '0', 'cmt': 'dir port invert mask:00000000'}, 4: {'val': '0', 'cmt': 'step enable invert, bool'}, 5: {'val': '0', 'cmt': 'l
imit pins invert, bool'}, 6: {'val': '0', 'cmt': 'probe pin invert, bool'}, 10: {'val': '3', 'cmt': 'status report mask:00000011'}, 11: {'val': '0.010', 'cmt': 'junction deviation, mm'}, 12: {'val': '0.002', 'cmt': 'arc tolerance, mm'}, 13: {'val': '0', 'cmt': 'report inches, bool'}, 20: {'val': '0', 'cmt': 'soft limits, bool'}, 21: {'val': '0', 'cmt': 'hard limits, bool'}, 22: {'val': '0', 'cmt': 'homing cycle, bool'}, 2
3: {'val': '0', 'cmt': 'homing dir invert mask:00000000'}, 24: {'val': '25.000', 'cmt': 'homing feed, mm/min'}, 25: {'val': '500.000', 'cmt': 'homing seek, mm/min'}, 26: {'val': '250', 'cmt': 'homing debounce, msec'}, 27: {'val': '1.000', 'cmt': 'homing pull-off, mm'}, 100: {'val': '250.000', 'cmt': 'x, step/mm'}, 101: {'val': '250.000', 'cmt': 'y, step/mm'}, 102: {'val': '250.000', 'cmt': 'z, step/mm'}, 110: {'val': '500
.000', 'cmt': 'x max rate, mm/min'}, 111: {'val': '500.000', 'cmt': 'y max rate, mm/min'}, 112: {'val': '500.000', 'cmt': 'z max rate, mm/min'}, 120: {'val': '10.000', 'cmt': 'x accel, mm/sec^2'}, 121: {'val': '10.000', 'cmt': 'y accel, mm/sec^2'}, 122: {'val': '10.000', 'cmt': 'z accel, mm/sec^2'}, 132: {'val': '200.000', 'cmt': 'z max travel, mm'}},)
          on_rx_buffer_percent: (0,)
                      on_write: ('$#\n',)
                        on_log: mygrbl: Polling thread started
             on_bufsize_change: (2,)
                on_vars_change: ({},)
           on_progress_percent: (0,)
                      on_write: ('G00Y3\n',)
                  on_line_sent: (1, 'G00Y3')
           on_progress_percent: (50,)
                      on_write: ('\n',)
                  on_line_sent: (2, '')
           on_progress_percent: (100,)
                       on_read: ('[G54:0.000,0.000,0.000]',)
                       on_read: ('[G55:0.000,0.000,0.000]',)
                       on_read: ('[G56:0.000,0.000,0.000]',)
                       on_read: ('[G57:0.000,0.000,0.000]',)
                       on_read: ('[G58:0.000,0.000,0.000]',)
                       on_read: ('[G59:0.000,0.000,0.000]',)
                       on_read: ('[G28:0.000,0.000,0.000]',)
                       on_read: ('[G30:0.000,0.000,0.000]',)
                       on_read: ('[G92:0.000,0.000,0.000]',)
                       on_read: ('[TLO:0.000]',)
                       on_read: ('[PRB:0.000,0.000,0.000:0]',)
           on_hash_stateupdate: ({'G54': (0.0, 0.0, 0.0), 'G55': (0.0, 0.0, 0.0), 'G56': (0.0, 0.0, 0.0), 'G57': (0.0, 0.0, 0.0), 'G58': (0.0, 0.0, 0.0), 'G59': (0.0, 0.0, 0.0), 'G28': (0.0, 0.0, 0.0), 'G30': (0.0, 0.0, 0.0), 'G92': (0.0, 0.0, 0.0), 'TLO': (0.0,), 'PRB': (0.0, 0.0, 0.0)},)
          on_processed_command: (0, 'G00Y3')
          on_rx_buffer_percent: (0,)
          on_processed_command: (1, '')
              on_job_completed: ()
          on_rx_buffer_percent: (0,)
          on_rx_buffer_percent: (0,)
                      on_write: ('$G\n',)
   on_gcode_parser_stateupdate: (['0', '54', '17', '21', '90', '94', '0', '5', '9', '0', '0.', '0.'],)
                       on_read: ('[G0 G54 G17 G21 G90 G94 M0 M5 M9 T0 F0. S0.]',)
          on_rx_buffer_percent: (0,)
                on_stateupdate: ('Run', (0.0, 0.724, 0.0), (0.0, 0.724, 0.0))
                on_stateupdate: ('Run', (0.0, 1.676, 0.0), (0.0, 1.676, 0.0))
                on_stateupdate: ('Run', (0.0, 2.508, 0.0), (0.0, 2.508, 0.0))
                on_stateupdate: ('Run', (0.0, 2.936, 0.0), (0.0, 2.936, 0.0))
                on_stateupdate: ('Idle', (0.0, 3.0, 0.0), (0.0, 3.0, 0.0))
                      on_write: ('$G\n',)
   on_gcode_parser_stateupdate: (['0', '54', '17', '21', '90', '94', '0', '5', '9', '0', '0.', '0.'],)
                       on_read: ('[G0 G54 G17 G21 G90 G94 M0 M5 M9 T0 F0. S0.]',)
          on_rx_buffer_percent: (0,)
.                        on_log: mygrbl: Please wait until polling thread has joined...
                        on_log: mygrbl: Polling has been stopped
                        on_log: mygrbl: Polling thread has successfully  joined...
                        on_log: iface_mygrbl: stop()
                        on_log: iface_mygrbl: JOINED thread
                        on_log: iface_mygrbl: Closing port
                        on_log: mygrbl: Please wait until reading thread has joined...
                       on_read: ('dummy_msg_for_joining_thread',)
                        on_log: mygrbl: Reading thread successfully joined.
               on_disconnected: ()

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Ran 1 test in 6.830s

OKDevelopmentInstall the Python version specified in the file.python-version.Dependencies are managed usingpipenv:pipinstallpipenv--user
pipenvinstall--devBuildingpipenvrunmakedist