Fast data logging

[mcgehee@noao.edu]

Dear all,

I am looking at archiving data from hardware systems at fast rates: 200Hz
or so. The following are some thoughts I've had about it and I wonder if
anyone else is also dealing with this issue.

I don't I would want to drive the logging at 200Hz via normal record processing.
What I had in mind was to have the record associated with the data create a 
standalone VxWorks task at init_record() which would be responsible for 
the communication with the device in question (PMAC?) at the 200Hz rate and store
it in an internal circular buffer.

>From the EPICS record processing point of view the record could be queried at
a slow rate via the normal EPICS scan task mechanism and the resulting array 
sent out to AR via channel access.


Pergrine
_______________________________________________________________________________
Peregrine M. McGehee			Controls Group	
Gemini 8-Meter Telescopes Project	PO Box 26732, Tucson, AZ 85726-2632
E-mail:	mcgehee@gemini.edu		Phone: (602) 321-3423