[d2n-analysis-talk] Trigger Questions

[Brad Sawatzky]

On Wed, 21 Oct 2009, David Flay wrote:

> I've been searching through the db_DL.dat file, and I found:
> 
> # LHRS trigger bit pattern(prescaled)
> # bit1       crate      4    13       0
> # bit2       crate      4    13       1
> # bit3       crate      4    13       2
> # bit4       crate      4    13       3
> # bit5       crate      4    13       4
> # bit6       crate      4    13       5
> # bit7       crate      4    13       6
> # bit8       crate      4    13       7
> # bit9       crate      4    13       8
> # bit10      crate      4    13       9
> # bit11      crate      4    13      10
> # bit12      crate      4    13      11
> # bit13      crate      4    13      12
> 
> # LHRS trigger latch pattern
> # lbit1       crate      4    13       13
> # lbit2       crate      4    13       14
> # lbit3       crate      4    13       15
> # lbit4       crate      4    13       16
> # lbit5       crate      4    13       17
> # lbit6       crate      4    13       18
> # lbit7       crate      4    13       19
> # lbit8       crate      4    13       20
> # lbit9       crate      4    13       21
> 
> Wouldn't I want these to be uncommented to see LHRS triggers?  Plots
> of the variables DL.LT1,...,DL.LT8 are labeled as 'trigger input copy
> LHRS ...' and they yield histograms (I was thinking these are the TDCs
> of the copies of each trigger), but do not agree with those of DBB.t*
> that Matt has (considering a coincidence run 1258).  However, DL.t*
> agrees with DBB.t* -- which makes sense as the DL.t* are labeled as BB
> trigger inputs.  In other words, it appears there's no bit pattern for
> the LHRS triggers? (or possibly using BigBite's)

Only one DAQ is running for coincidence runs (handles all triggers), so
there is only one set of trigger bits.  In this case the "BB" TDC was
used (mostly because the trigger supervisor was in the BB DAQ weldment).

There was a redundant set of signals that fed up to the LHRS hut and
plugged into a TDC there.  Those are the DL.LTX you were looking at.

-- Brad

-- 
Brad Sawatzky, PhD <brads at jlab.org>  -<>-  Jefferson Lab / Hall C / C111
  Ph: 757-269-5947 -<>- Pager: 757-584-5947 -<>- Fax: 757-269-7848
The most exciting phrase to hear in science, the one that heralds new
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