Initial Pulser Testing of a DAQ slice.

A first try at a slice of the digitizing and DAQ readout for
the PSEC testbeam has been assembled and tested at ANL.
It consists of a pulser driving a AD411 adc and a FERA
Camac memory readout by a Wiener CC-USB camac interface
to a Linux server. The camac data is acquired by a small
C program and written to disk. A small C++ program reads
the disk raw data, reformats the data into a ntuple. The
ntuple is transformed and stored as a standard ROOT tuple
for futher offline analysis. 

As a test of both the hardware and software a series of
runs were taken in which the pulser amplitude and repitition
rate were varied over a range:
	2.5Volt pulse: with 0,6,12 and 18 db attenuation
	Rep-rate: 1msec, 0.5 msec and 0.1 msec.

Useful tests would be to check the 
	1) time (adc) resolution
	2) time (adc) linearity
	3) rate effects
	4) search for correlations and annomolies!

To this end a ROOT ntuple which combines all the runs is
now available. PSECpulserData.root (960446 bytes)
The columns are
runNumber:		int
lineID:			int (sequence number of event in DAQ buffer)
t1:			float (Linux microsec timer (sec) at start of buffer read)
t2:			float (Linux microsec timer (sec) at completion of a buffer read)
adcValue:		int	AD411 digit word
pulserVoltage:		float	volts
pulserAttenDB:		float (db of fixed attenuator inserted)
pulserPeriod		float ( milliseconds)


clipped from run logbook...
[may@atlas2 Nearline]$ more  data/run_logbook.log
Run Setup: RunNumb=50 PulseVolt=2.5 AttenDB=0 Period=1.0 NumbNoReads=25
Run Setup: RunNumb=51 PulseVolt=2.5 AttenDB=6 Period=1.0 NumbNoReads=25
Run Setup: RunNumb=52 PulseVolt=2.5 AttenDB=12 Period=1.0 NumbNoReads=25
Run Setup: RunNumb=53 PulseVolt=2.5 AttenDB=18 Period=1.0 NumbNoReads=25
Run Setup: RunNumb=54 PulseVolt=2.5 AttenDB=0 Period=0.5 NumbNoReads=25
Run Setup: RunNumb=55 PulseVolt=2.5 AttenDB=6 Period=0.5 NumbNoReads=25
Run Setup: RunNumb=56 PulseVolt=2.5 AttenDB=12 Period=0.5 NumbNoReads=25
Run Setup: RunNumb=57 PulseVolt=2.5 AttenDB=18 Period=0.5 NumbNoReads=25
Run Setup: RunNumb=58 PulseVolt=2.5 AttenDB=0 Period=0.1 NumbNoReads=25
Run Setup: RunNumb=59 PulseVolt=2.5 AttenDB=6 Period=0.1 NumbNoReads=25
Run Setup: RunNumb=60 PulseVolt=2.5 AttenDB=12 Period=0.1 NumbNoReads=25
Run Setup: RunNumb=61 PulseVolt=2.5 AttenDB=18 Period=0.1 NumbNoReads=25


Although the raw data and data products formats are far from being fixed
this exerise provides the kind of data which will be record and available
from the testing and testbeam hardware.

We expect similar testing data to be acquired as the hardware is assembled
into a larger and more complete system capable of supporting the test
beam configuration. 

Ed May
April 25, 2008