1) Peter Hansen was asking you for the code AFTER the "ser.readline()" not BEFORE!! the code you have originally posted here
2) the best way how to examine if your code works is to try to write some simplest code as possible first (not buttons, not GUI etc..., just a simple code) (all this suggestions were already mentioned in one of your previous postings, see http://tinyurl.com/zz3s5) Regarding to your questions in this posting I think you can try something like: import serial ser=serial.Serial(0, 9600, 8, "E", stopbits=2, timeout=1) while 1: print s.readline() In your original code you have posted here, you read one line from the serial port only. It means the code reads byte by byte from the serial port till the "end of line" byte ('\n') is recognized. Than the reading stops and after that the whole code is finished because no other code lines after the ser.readline(). If no data present on the serial port for longer than "timeout" defined, it will stop reading serial port and the code finishes as well. 3) please note, you can define serial port as following as well which is ,IMHO, more readable: ser=serial.Serial(0, 9600, 8, "E", stopbits=2, timeout=1) (it was recommended to you in above mentioned posting as well) You can find plenty of examples on http://pyserial.sourceforge.net/ in the "Examples" paragraph. Try to study and search before you ask. HTH Petr Jakes -- http://mail.python.org/mailman/listinfo/python-list
