Re: PCI-DAS1602/16 with pacer and external trigger

On Wed, Jul 23, 2003 at 01:12:50PM -0700, Michael Borland wrote:
> I'm trying to use the Measurement Computing PCI-DAS1602/16 with both an 
> A/D pacer and an external trigger to start the scan.  My application is 
> that I want an external trigger to start the scan, with samples taken 
> for all channels in burst mode each time the pacer trigger comes in.
> 
> I thought I could do this with
> cmd->start_src =        TRIG_EXT;
> cmd->scan_begin_src =   TRIG_EXT;
> cmd->convert_src =      TRIG_NOW;
> cmd->scan_end_src =     TRIG_COUNT;
> cmd->scan_end_arg =     n_chan;
> cmd->stop_src =         TRIG_COUNT;
> cmd->stop_arg =         n_scan;
> 
> However, comedi_cmd_test tells me that I have a source conflict.  As I 
> understand the board, the start command can only use the external 
> trigger, while the scan_begin command can only use the A/D pacer, so 
> there should be no conflict.  TRIG_EXT means something different for 
> those two commands, or should.
> 
> Am I misunderstanding something?

Yes, you should be using start_src = TRIG_NOW.



dave...

Received on 2003-07-23Z20:01:03