range setting, continuous streaming with PCI-DAS4020/12

• From: Kurt Rosenfeld <hardware_at_ee.ccny.cuny.edu>
• Date: Sat, 28 Jul 2007 15:53:27 -0400

Hello Everyone,

We have here a Computer Boards PCI-DAS4020/12 card.  The cmd.c 
demo program works as is (Comedi version 0.7.73, Linux 2.6.18.8), 
but I have had trouble modifying it to do what we need it to do.

Problem 1: The range setting doesn't seem to do anything.   
The demo/info program reports two range settings, like so:

  max data value: 4095
  ranges:
    all chans: [-5,5] [-1,1]
  command:
    start: now|ext
    scan_begin: timer|other
    convert: now|timer
    scan_end: count
    stop: none|count|ext

But setting range to 1 doesn't make the input scale run from 
-1 to 1 volt.  

Problem 2: I can't seem to get the cmd.c program to do continuous
streaming with our card.  The following modifications did not do it.
The program still outputs 32768 samples and then exits.

 //cmd->stop_src = TRIG_COUNT;
 cmd->stop_src =   TRIG_NONE;
 //cmd->stop_arg = n_scan;
 cmd->stop_arg =   0;

Suggestions?  thanks, -kurt

Received on 2007-07-28Z18:53:27