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Message ID: 5     Entry time: 11 Jan 2019 11:07
Author: Thomas 
Type: Routine 
Category: Digitizer 
Subject: Data corruption for ADC channels 
I modified the analyzer so that it shows data from all four modules.

I find that there is evidence of corruption of the V1725 ADC data on a couple channels.   You can see an example of a waveform with corruption in the attachment.  You see that there seems to be a bunch of fluctuations of exactly 16 
ADC counts, which seems unphysical.  So far I see this problem in these channels:

module 0, ch 0
module 0, ch 1
module 0, ch 13
module 1, ch 4
module 3, ch 6

I saw corruption similar to this on the V1730 readout.  CAEN does have a scheme for ADC calibration (by poking a register), which worked well for the V1730.  I thought that I implemented this ADC calibration for the V1725, but I might 
have messed it.  I'll look at this again.
Attachment 1: dsproto_corrupt.gif  33 kB  | Hide | Hide all
dsproto_corrupt.gif
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