nanoDLP

KevinLan

Member

Registered: 2016-11-26

Posts: 4

Serial port could not be activated Unknown baud rate 250000

I got a DIY LCD uv resin 3d printer, which use marlin and baud rate 25000.
Currently install beta version nanodlp to my respberry 3 pi.
But I can't get my printer connected, it shows error:

Serial port could not be activated Unknown baud rate 250000.

I'v tried to connect my printer use python 2.7.9 and pyserial 3.2.1

import serial
ser = serial.Serial('/dev/ttyACM0', 250000)
ser.write('G28\n\r')

works perfectly.

Any help?

Thanks.

Shahin

Administrator

Registered: 2016-02-17

Posts: 3,546

Re: Serial port could not be activated Unknown baud rate 250000

I have not seen this error before. Could you try patched marlin, link is available on our download page.

KevinLan

Member

Registered: 2016-11-26

Posts: 4

Re: Serial port could not be activated Unknown baud rate 250000

I have not seen this error before. Could you try patched marlin, link is available on our download page.

I use your patched mariln with baud rate 115200 ,G28 works.
But when I change baud rate to 250000bps , the log shows same error again.

My board is common integrated Atmega 2560 and RAMPS 1.4 board MKS-Mini,
http://reprap.org/wiki/MKS_MINI

Shahin

Administrator

Registered: 2016-02-17

Posts: 3,546

Re: Serial port could not be activated Unknown baud rate 250000

You cannot just change baud rate. You need to recompile your firmware for the baud rate you want.

KevinLan

Member

Registered: 2016-11-26

Posts: 4

Re: Serial port could not be activated Unknown baud rate 250000

You cannot just change baud rate. You need to recompile your firmware for the baud rate you want.

Hi Shahin,

Sorry, I reply it too short.

First, I download patched marlin firmware and write it into my board use Arduino IDE. Which it works for nanoDLP in 112500bps setting (no error found), and success running G28 command with terminal in nanoDLP.

Then I change the baud rate setting form 115200 to 250000 in configuration.h in Arduino IDE, save and rebuild it , write into my board, connect my board and raspberry pi 3 with usb cable, start nanoDLP. The arduino board didn't connect to raspberry pi 3 even I use 250000 bps setting in nanoDLP's machine setting (of cause won't work in other bps setting), the error message "Serial port could not be activated Unknown baud rate 250000" was shown when I check the log in nanoDLP.

Best Regards.

Shahin

Administrator

Registered: 2016-02-17

Posts: 3,546

Re: Serial port could not be activated Unknown baud rate 250000

Hi Kevin,

Thanks, you point out to the issue in our source code.
Apparently raspberry does not support higher than 115200 speed. (http://fw.hardijzer.nl/?p=138) And require recompiling kernel to achieve higher speed. I will remove option from nanodlp.

I do not know why you would like to achieve higher speed as currently even with 9600 speed we would not effect speed of printing.

KevinLan

Member

Registered: 2016-11-26

Posts: 4

Re: Serial port could not be activated Unknown baud rate 250000

Hi Kevin,

Thanks, you point out to the issue in our source code.
Apparently raspberry does not support higher than 115200 speed. (http://fw.hardijzer.nl/?p=138) And require recompiling kernel to achieve higher speed. I will remove option from nanodlp.

I do not know why you would like to achieve higher speed as currently even with 9600 speed we would not effect speed of printing.

I am definitely sure the raspberry pi 3 can support baud rate at 250000 bps, because I had used python script on raspberry pi 3 to connect marlin at 25000bps and run G28, but as you mention, that makes no different even I can reach higher speed.

Anyway , I made my patched marlin use 115200bps (the seller of my machine didn't provide the source code of marlin he used) and problem is solved.

Thanks a lot.