Newbie - help request with serial line (termios?) setup in Python 2.2

Bill Gillespie billintucson at yahoo.com
Sun Aug 4 07:44:33 CEST 2002


Chris Liechti <cliechti at gmx.net> wrote in message news:<Xns9258CF6662B33cliechtigmxnet at 62.2.16.82>...
> billintucson at yahoo.com (Bill Gillespie) wrote in 
> news:4860ce4f.0207271004.4cbc8880 at posting.google.com:
> > I'm trying to open a serial line on a SunOs using python 2.2.
> > I'm new to programming, and fairly new to unix/linux. I have the two
> > pink Oreilly Python books and have read a couple of tutorials - but I
> > am a newbie.
> 
>  welcome
> 
> > After much googling (there is not a lot of novice python/unix/termios
> > info out there) - this is what I think? I should be doing....
> > 
> > Open the line
> > Configure the line? termios??
> > Communicate with the line (ASCII charachters < > at 4800)
> > Close the line
> 
> ok, i make it short... you could use my library http://pyserial.sf.net
> if, for some reason, you still want to do it by hand, you can at least look 
> at the sources.
> 
> (you may need to specify the port by name:
> s = serial.Serial('/dev/ttyC43', baudrate=4800, timeout=1))
> 
> chris


I had some great help from the author of PySerial on this. There was
no
need to interact with termios at all. All I had to do was install this
module (PySerial) and set up my serial line with the proper: 

                   buad rate, 
                   stop bits,
                   and
                   data bits, 

Anyone who needs to interact with a serail line using linux as I am -
can use this very helpful module (PySerial).

Links and a code example of the interaction I had - below.... 

------------------------------------------------------------

Web site:
http://pyserial.sourceforge.net/
(setup and usage help overview)

CVS repository:
http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/pyserial/pyserial/
         ************************************************************************
                    
Setting up and opening the serial line on a Sun:
                    
ser=serial.Serial('/dev/ttyC43', 4800, 7,1,timeout=1) for cin ttyC43
                    
ser=serial.Serial('/dev/ttyC43', 4800, timeout=1)     for cin ttya
                    
************************************************************************
        
       >>> import serial
       >>>
       >>> ser=serial.Serial('/dev/ttyC43', 4800, 7,1,timeout=1)
       >>>
       >>> ser.write('dump_oftc\r')
       >>>
       >>> ser.readlines(400)
       ['dump_oftc 116  150  99  168  304  XXX  175  242  166  174 
172  173 163        234  233  236  OK\r\n']

       >>>
       >>>
       >>>
       >>> ser.write('oftv\r')
       >>>
       >>> ser.readlines(400)
       ['oftv \r\n', 'OGS OGR OXS OXR OPR OSP AMB spr tb1\r\n', '58 74
97 167 		       152 40 172 238 cp=234  \r\n', '\r\n', 'FGS FGR FT1 FT2
FT3 spr spr spr           tb2\r\n', '82 87 168 174 161 231 234 237
cp=241  \r\n', '\r\n', 'OK\r\n']
                    
                   ....................................
                   finding the current set point for oil
                   .....................................
                    
                   >>> ser.write('osetpoint?')
                   >>>
                   >>> ser.write('\r')
                   >>>
                   >>> ser.readlines(400)
                   ['osetpoint? 5 OK\r\n']
                   >>>
                    
                   .......................................
                   Finding the current setpoint for floor
                   ......................................
                    
                    
                   >>> ser.write('fsetpoint?')
                   >>>
                   >>> ser.write('\r')
                   >>>
                   >>> ser.readlines(400)
                   ['fsetpoint? -5 OK\r\n']
                    
                   ......................................
                   end code examples....


Many thanks to Chris Liecht for his help,
and making this software available! 

     Cheers, 

           Bill



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