Python serial port

[nipunreddevil]

How can i use usb-serial converter to perform serial operations using python.pySerial does not mention it ,i guess?And how can we view our ports in linux as we do using device manager in Windows?

[jpkotta]

Install the python-serial package. Then in your program:


import serial
ser = serial.Serial()
ser.port = "/dev/ttyUSB0" # may be called something different
ser.baudrate = 115200 # may be different
ser.open()
if ser.isOpen():
ser.write("hello")
response = ser.read(ser.inWaiting())


In Linux, serial ports are named /dev/ttySx or /dev/ttyUSBx, where "x" is a number.

[nipunreddevil]

Thanks,so i just plug in my usb-serial cable and assume i am working with serial port.How do i know which serial/usb port i am using

[jpkotta]

Thanks,so i just plug in my usb-serial cable and assume i am working with serial port.How do i know which serial/usb port i am using

For a USB serial port adapter, they are numbered in the order that they enumerate. I think there is a way to give a given device the same number every time, but I've never bothered to learn how. Just after plugging it in, you will see some messages in /var/log/messages (or use dmesg) that tell you what number it got.

[nipunreddevil]

Thanks again.Now what i intend to do is write data serially and receive data serially continuously using pyGTK.How shall python programming for this be done.if i use serialin waiting ,i guess it will keep on receving but will not write

[nipunreddevil]

I tried what you told and it worked in idle but when i use it within Geany or Gedit,i get following errors
Traceback most recent call last
File "serial.py",line 3,in module
import serial
File"/home/nipun/serial.py",line 5,in module
ser=serial.Serial()
Attribute error:module object has no attribute Serial

how can i make it work?

[jpkotta]

Did you name your file serial.py? You can't use that name*. Python tries to import files in the current directory (i.e. serial.py) before other locations, so it's not importing the serial.py from python-serial.

* You could use that name, but it requires a workaround, and isn't recommended.

[nipunreddevil]

changing name has not helped,get same errors for prog.py now
Here is prog.py

import serial
ser=serial.Serial()
ser.port="/dev/tyUSB0"
ser.baudrate=9600
ser.open()
ser.write("hi")

[nipunreddevil]

Thanks,got it working
Had forgotten to delete previous file -serial.py

[topdoguk]

As a newbie i have had exactly the same problem, been tearing my hair out for days.
I had also created a file called serial.py once I deleted this file my program run perfectly.

Thanks for this posting. I bet there's plenty more people out there caught out by this one!

[nipunreddevil]

Yes such things should be mentioned in PySerial website

[jpkotta]

Yes such things should be mentioned in PySerial website

They really shouldn't, if you're referring to the problems caused by having a source file named serial.py. This has absolutely nothing to do with PySerial; it has everything to do with how Python works. It would be like library authors documenting the fact that you need to use syntactic indentation (http://en.wikipedia.org/wiki/Python_(programming_language)#Indentation) when you use their libraries.

[LanceRooke]

Ok, how do I use this script to get my touchscreen working?

http://pastebin.com/yLQ1hbwt

It's from trendystephen article on getting touchscreen to work on Ubuntu on the Fujitsu B3020D.