Connection timeout -MKS Gen L

I need some help please,
I saw some issues like mine but none for a MKS gen L, I looked into the others trying to look for any clues to my situation but couldn't make any progress

I had no problem the first time I flashed but a week ago it started to act funky and wouldn't let me upload new Klipper printer.cfg files so i decided to flash again Octoprint, now I'm getting this 'timeout connection' error message

  • i changed usb cable (short original one)
  • lowered baudrate
  • switched the usb port
  • bought a new micro sd (32gb)
  • I even tried with a different board

rpi 3b+
mks gen L
Tronxy x5s

Serial log looks like:
2019-06-26 06:01:27,967 - Connecting to: /dev/ttyUSB0
2019-06-26 06:01:27,989 - Changing monitoring state from "Offline" to "Opening serial port"
2019-06-26 06:01:27,995 - Connected to: Serial<id=0x6ef2edf0, open=True>(port='/dev/ttyUSB0', baudrate=250000, bytesize=8, parity='N', stopbits=1, timeout=10.0, xonxoff=False, rtscts=False, dsrdtr=False), starting monitor
2019-06-26 06:01:27,997 - Changing monitoring state from "Opening serial port" to "Connecting"
2019-06-26 06:01:28,013 - Send: N0 M110 N0*125
2019-06-26 06:01:38,999 - There was a timeout while trying to connect to the printer
2019-06-26 06:01:39,009 - Changing monitoring state from "Connecting" to "Offline"
2019-06-26 06:01:39,021 - Connection closed, closing down monitor

octoprint (1).log (98.7 KB) serial.log (296 Bytes)

Have you tried setting your firmware to use a lower baudrate. I have one printer that just can't keep up with 250000 for some reason. Also, what happens when you just set the port and baudrate to auto?

Thanks for helping Terry,
I have tried auto and I tried also the 125 baudrate but it ends the same with a connection error

Why do you want to change these? These work on my setup which is pretty much identical to yours except that my printer is an Ender 3 but with an MKS Gen L.
You seem to have tried everything I would've tried. Except replace the RPi. Any chance you have another one you can try? If not, it may be worth buying another one. It doesn't hurt to have a spare lying around.

I was thinking about it, I would however like to know if it is a faulty RPi or if there is something in the code that could be changed to solve it

I'm starting to belive that there is something to do with traces of older installition interfering - now I have this problem with the board Klipper was already installed on but not with a new one..

XON/XOFF is a software flow control that is not used on every serial connection.
RTS/CTS and DSR/DTR are for hardware
flow control and require more connections.
These flow controls belong tor the RS232 standard:

But like I suspected it was due to the older installation, I reinstalled Klipper and the problem was gone - no idea how to explain it because of lack of knowledge :man_shrugging:t2: