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python error serial port

Hi All
Trying to help someone out in Inkscape and sending the initial test file through - connectivity appears to be com3 via usb. Here's the error produced which would seem to say it isn't finding the com port

Any pointers on things to try?


Traceback (most recent call last):

File "laser.py", line 3367, in <module>


File "inkex.py", line 283, in affect


File "laser.py", line 3361, in effect

if self.options.stream == True : self.gcodetocontroller((self.serial_ports()),((self.options.directory+self.options.file)),((self.options.directory+self.options.file+"_log")))

File "laser.py", line 3106, in gcodetocontroller

s = serial.Serial(port[0],BAUD_RATE)

IndexError: list index out of range


Hi Bryan, you could change the laser.py or raster2gcode.py scripts and assign directly 'com3' to the port.

The best thing is to find the root cause: does it happen in both plugins? Can you use cncjs (gcode sender) and that works? Or do non of the programs interface? If so, then you can move to the usb cable (swap and try, some cables are actual not usb cables but charger leads). Can you use different usb ports or pc's to test? If everything fails then you might have a broken gerbil usb port. Check if the 2 usb jumpers are set on the right position on the R4 controller board (the pcb below the k40 shield).

Let me know what your findings are so we can pinpoint the issue.

Cheers, Paul awesome.tech

Hi Paul

Funnily enough my follow up question was going to be how do you hard code com ports.

This wasn't for my board but checking for someone in America who contacted me via Facebook, so he has been my eye's on all of this. We eliminated a USB cable a couple of days ago. It was only when I thought on that you can get those size of usb cables purely for charging purposes i.e. just two pins connected for mobile phones...

Anyway yesterday I asked him to try lightburn and see if we could narrow things down further still. He set the port manually and was away, so success 🙂 He was over the moon too!

Hopefully this post will help other people if they stumble upon similar problems.

My turn for fitting the board this weekend.


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