Re: Progress on Compressors

[Fred Gray <fegray@socrates.berkeley.edu>]

> A real macro dead time free mode is possible if one uses the previous compressor
> mode but then the DAQ must poll or be interrupted at the half full of the SIS FIFO
> sending a TIMECLEAR signal at every readout and an INHIBIT level generated only
> when the DAQ is stopped or overloaded

Dear Rene,

Thanks for your comments, which I'm still trying to digest.  My overall question
still remains: as you said (above), a deadtime-free readout is possible with the 
previous mode.  Tom and I now have the software set up to continuously poll on 
the CAEN TDCs, and presumably the same technique would work with the SIS FIFO.  
Meanwhile, this new mode introduces difficult-to-avoid deadtime.  I really am 
curious about what led to this change.

I don't think we have benchmarked the VME transfer rate from the SIS FIFO, but
my guess is 5 to 10 MB/s, i.e. less than 20.

Thanks,

-- Fred

-- Fred Gray / Visiting Postdoctoral Researcher                         --
-- Department of Physics / University of California, Berkeley           --
-- fegray@socrates.berkeley.edu / phone 510-642-4057 / fax 510-642-9811 --