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User name R. Michaels
Log entry time 16:49:18 on October 09, 2009
Entry number 294034
keyword=ADC18 test crate: important bug fix (fixes oversampling)
Thanks to Dave Abbott and Ed Jastrzembski of the DAQ group, a
simple bug was found in adc18_reset which caused the "buffer full"
bit to remain stuck with the "new" ADC18 software. Instead of
writing to "csr" the code wrote to "ctrl" -- a mistake.
The bug was found by reproducing the symptoms in the test crate
and showing the details to Dave and Ed.
Reminder: about 6 weeks ago we made improvements to our ADC18
library which dealt more correctly with the state machine logic,
leading to the "new" ADC18 software. However, this had a fault
that when the DAQ crashed the a "buffer full" condition remained on,
which could lead to corrupted data. We sadly had to roll back our
old code, which mostly works (we've been taking data for weeks with
little complaint) -- but not with oversampling.
Now that we have this fix we can try oversampling with beam and our
full system -- perhaps next week ? The new code should make overs-
ampling work and should have zero "bad1" data or glitches. I hope.
At the moment, the test crate has 5 ADC18 which work well with
A copy of this log entry has been emailed to: mercado,paschke,rom,kkumar