Re: streamdevice

[Rod Nussbaumer <bomr@triumf.ca>]

Or he may mean channels within a device or module, such as channels 
within an oscilloscope or multichannel digitizer. In such cases, the 
method should be documented by the vendor of the device. There is no 
generic method or streamDevice-specific method for performing such 
selections.
A couple of things may be worth noting. In some cases, there is a 
specific SCPI command that effectively says 'for all subsequent 
commands, use channel n'. Where you are monitoring more than one channel 
on a periodic schedule, you can put that command into a single 
streamDevice protocol that may contain other commands that relate to 
that specific channel. You would probably do so for a number of 
protocols where you want to address specific channels. Moreover, a 
single protocol may be contrived that will work for all channels, where 
the channel number (or other identifier) is a macro variable (like \$1) 
that is passed to the protocol. The channel identifier might also be a 
PV such as an analog record or a multibit binary record, and this can be 
referenced an decoded in the protocol.

If Sebastian has a different meaning for the question, he should 
rephrase and expand on his intention.

   ---   rod.



On 05/22/2013 07:18 AM, Mark Rivers wrote:
> I think he probably means the asyn "addr" field, used to select a specific address or channel of a device.
>
> Mark
>
> ________________________________________
> From: tech-talk-bounces@aps.anl.gov [tech-talk-bounces@aps.anl.gov] on behalf of Dirk Zimoch [dirk.zimoch@psi.ch]
> Sent: Wednesday, May 22, 2013 4:24 AM
> To: tech-talk@aps.anl.gov
> Subject: Re: streamdevice
>
> On 21.05.2013 18:45, Sebastian Matkovich wrote:
> > is it possible that you cannot access specific channels of a device
> > through streamdevice? or does somebody know how to do that?
>
> What do you mean with "specific channels of a device"?
>
> Dirk