serial usb connection to arduino mega 2560r3

[sybdezeiler]

Hi all.
Being a novice I posted an earlier thread here..https://forum.openmarine.net/showthread.php?tid=6985..

I found the solution for the limping installation by installing SWIG prior to the pypilot installation on openplotter v4 headless image.

Next issue I encountered is the serial connection from Arduino mega 2560r3 to rpi 4b.
Created the alias, but no Rx/Tx traffic is happening. Sometimes the Rx is flashing. I could use some hints to make progress with yhis.
Nothing attached so far to the arduino. Motorcontroller ordered more than a week ago, but still waiting for that. But in the meantime I would like to advance.

[seandepagnier]

What is the specific question other than me being slow to ship orders?

[sybdezeiler]

What is the specific question other than me being slow to ship orders?

Sean,
no worries about the delivery! Still enough to be done in the meanwhile.

As far as the arduino/rpi issue concerns:

So far I saw communication in the autopilot interface for about 5 seconds and after that none.
Short flashing of 'arduino' and 'sync' and something about the battery.

On the arduino I have the motor.ino loaded.

Connection is USB A-USBB. /dev/ttyACM0 with an alias I created. In the beginning I had the connection added to signalK as well, but got device busy errors and read somewhere that only the serial connection with an alias for Pypilot had to be added. Stuck at that point. Checked some permissions on serial devices and also the presence of the device alias in serialports.

Maybe you have some hints for further investigations?

[sybdezeiler]

What is the specific question other than me being slow to ship orders?

Sean,
no worries about the delivery! Still enough to be done in the meanwhile.

As far as the arduino/rpi issue concerns:

So far I saw communication in the autopilot interface for about 5 seconds and after that none.
Short flashing of 'arduino' and 'sync' and something about the battery.

On the arduino I have the motor.ino loaded.

Connection is USB A-USBB. /dev/ttyACM0 with an alias I created. In the beginning I had the connection added to signalK as well, but got device busy errors and read somewhere that only the serial connection with an alias for Pypilot had to be added. Stuck at that point. Checked some permissions on serial devices and also the presence of the device alias in serialports.

Maybe you have some hints for further investigations?

Some more info on the issue:
When stopping pypilot and only running pypilot_servo the logging seems ok without errors like:

nmea probe ('/dev/serial/by-id/usb-Arduino__www.arduino.cc__0042_751313139323512101B1-if00', 38400)
nmea probe ('/dev/serial/by-id/usb-Arduino__www.arduino.cc__0042_751313139323512101B1-if00', 4800)
servo probe ('/dev/serial/by-id/usb-Arduino__www.arduino.cc__0042_751313139323512101B1-if00', 38400) 3852.181802421
nmea probe ('/dev/serial/by-id/usb-Arduino__www.arduino.cc__0042_751313139323512101B1-if00', 38400)
nmea probe ('/dev/serial/by-id/usb-Arduino__www.arduino.cc__0042_751313139323512101B1-if00', 4800)
servo probe ('/dev/serial/by-id/usb-Arduino__www.arduino.cc__0042_751313139323512101B1-if00', 38400) 3876.781888054
servo probe ('/dev/serial/by-id/usb-Arduino__www.arduino.cc__0042_751313139323512101B1-if00', 38400) 3891.181868387

when using the openplotter interface and set IMU only still no errors
however when enabling autopilot next logging lines appear:

failed to open ('/dev/serial/by-id/usb-Arduino__www.arduino.cc__0042_751313139323512101B1-if00', 38400) for nmea data [Errno 16] could not open port /dev/serial/by-id/usb-Arduino__www.arduino.cc__0042_751313139323512101B1-if00: [Errno 16] Device or resource busy: '/dev/serial/by-id/usb-Arduino__www.arduino.cc__0042_751313139323512101B1-if00'
nmea probe ('/dev/serial/by-id/usb-Arduino__www.arduino.cc__0042_751313139323512101B1-if00', 4800)
failed to open ('/dev/serial/by-id/usb-Arduino__www.arduino.cc__0042_751313139323512101B1-if00', 4800) for nmea data [Errno 16] could not open port /dev/serial/by-id/usb-Arduino__www.arduino.cc__0042_751313139323512101B1-if00: [Errno 16] Device or resource busy: '/dev/serial/by-id/usb-Arduino__www.arduino.cc__0042_751313139323512101B1-if00'
server add socket ('127.0.0.1', 35024) 4025.043571157

I don't understand this.

some dmesg lines:

dmesg -w:
486.682911] usb 1-1.3: USB disconnect, device number 3
[  527.860370] usb 1-1.3: new full-speed USB device number 4 using xhci_hcd
[  527.963341] usb 1-1.3: New USB device found, idVendor=2341, idProduct=0042, bcdDevice= 0.01
[  527.963358] usb 1-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=220
[  527.963362] usb 1-1.3: Manufacturer: Arduino (www.arduino.cc)
[  527.963366] usb 1-1.3: SerialNumber: 751313139323512101B1
[  527.968760] cdc_acm 1-1.3:1.0: ttyACM0: USB ACM device

Then I wrote an arduino sketch and a py script to check communication and that's working fine between rpi and arduino USB connection. The builtin led on the arduino blinks on receiving a message from the rpi and replies with "yes here is the arduino"

So my conclusion is that serial usb connection is ok, but pypilot code does something that I don't understand. My knowledge stops there.
Please advise.

[seandepagnier]

It seems like a different process or program is accessing the serial port, this is what the "device or resource busy" hint means