comedi_data_read with python

Hi all,

I have a problem with comedi_data_read(...) function using python.
I've done this simple example, taken from demo dir of the comedilib
tarball, but it doesn't work:

###############################################

import comedi as c
import time

subdev = 0
chan = 0 
range = 0 
aref = 0 

cf = c.comedi_open('/dev/comedi0')
maxdata = c.comedi_get_maxdata(cf, subdev, chan)
cr = c.comedi_get_range(cf, subdev, chan, range)
data = 100

print "Writing data"
if c.comedi_data_write(cf, subdev, chan, range, aref, data) == -1:
  print "Error writing device"

print "Reading data"
if c.comedi_data_read(cf, subdev, chan, range, aref, data) == -1:
  print "Error reading device"

volts = c.comedi_to_phys(data, cr, maxdata)
print '%d %g\n'%(data, volts)

###############################################################


this is the error from python interpreter:

  Traceback (most recent call last):
    File "tut2.py", line 34, in ?
        if c.comedi_data_read(cf, subdev, chan, range, aref, data) == -1:
        TypeError: Type error. Expected _p_lsampl_t
      
in C library lsampl_t is an un unsigned int, it seems that python
doesn't like my "data" variable ?

Would you please help me?

Thank you very much

Marco Pagnanini
 
-- 
Marco Pagnanini
http://www.marcopagnanini.it && http://www.cmlug.org
info<AT>marcopagnanini.it && tmp<AT>cmlug.org

Received on 2004-08-02Z15:58:09