Re: Proposed change in asyn - request for comments

["Williams Jr., Ernest L." <ernesto@slac.stanford.edu>]

Sent from my iPhone

On Jun 1, 2012, at 7:57 AM, "Andrew Johnson" <anj@aps.anl.gov> wrote:

> Hi Bruce,
> 
> On 2012-05-31 Bruce Hill wrote:
>> 
>> My concern was that overloading the TSE field to contain EVR Event codes
>> would be inappropriate for a module like asyn that is used by many sites
>> that don't use EVR's.
> 
> The TSE and TSEL fields were originally /designed/ for use with timing system 
> event codes.  The Record Reference Manual describes the TSE field thus:
> 
>    This indicates the mechanism to use to get the time stamp. '0' - call
>    get time as before '-1' - call the time stamp driver and use the best
>    source available. '-2' - the device support provides the time stamp
>    from the hardware. Values between 1-255 request the time of the last
>    occurrence of a generalTime event.
> 
>  https://wiki-ext.aps.anl.gov/epics/index.php/RRM_3-14_dbCommon
> 
> I agree that this mechanism is not currently much use on systems that don't 
> use an event timing system, although it would be quite feasible to write a 
> plugin for the generalTime event subsystem that provides global event times 
> from UDP packets.
That is really a good idea :)
Then windows-based systems can pick up pulseIDs over the network 
Or at least for systems that don't have special timing hardware on the client side

Cheers
Ernest



> 
> - Andrew
> -- 
> Never interrupt your enemy when he is making a mistake.
> -- Napoleon Bonaparte