Re: summary of 1/29/03-1/30/03 access

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From: Frank Geurts (geurts_at_rice.edu)
Date: Mon Feb 03 2003 - 15:44:50 EST

> goals:
> A: specific adc/tdc mapping problem in tofr - must locate & fix!

did something change w/ the last TOFr-TDC unit? It appears to be running
at 100ps/channel: the strobed data is at ~470 which is about half of the
original values that were at ~960. The non-strobed data is consequently
0. A problem in the TDC-start could explain only the 0s but not the
strobed signals. I traced down the previous DMA errors but they were
TOFp-ADC related (see below).

> B: scattered problem channels in TOFp that could be fixed given
> the opportunity.... when this travel was booked there was no intention
> to address the scattered failed chs in tofp, but (!):

could you send me a list of the locations of the HVC before the change
(i had a list of some 5 HVCs of which we were not sure which TOFp
channel they served)

> amazingly, i was able to get the nederlander to wake up at
> 8am central thursday to test the new cells.

  LOL

item D -- unresolved yet
  Ever since the last access I am seeing DMA errors for TOFp-ADC (see
below). The logfiles cover the period
log2: Jan31,08:19 -- Feb1,08:18
log1: -- Feb2,08:18
log0: -- Feb3,08:18
log: -- Feb3,15:11

i don't remember seeing them in earlier logs. Last year we related the
TOFp DMA errors to Q-suppresion because of the negative pedestals. Can
you see something like that in the localmon TOFp ADC spectra?

We could consider switching to a slower channel-by-channel readout to
identify which of the channels causes this problem.

[tofp_at_tofp log]% grep DMA det.log*
det.log:[tof02 14:21:49] (getdata): OPERATOR: getdata.cxx [line
1199]: DMA read TOFp ADC error

det.log.0:[tof02 02:11:46] (getdata): OPERATOR: getdata.cxx [line
1199]: DMA read TOFp ADC error
det.log.0:[tof02 03:19:38] (getdata): OPERATOR: getdata.cxx [line
1199]: DMA read TOFp ADC error

det.log.2:[tof02 09:23:53] (getdata): OPERATOR: getdata.cxx [line
1199]: DMA read TOFp ADC error
det.log.2:[tof02 04:48:07] (getdata): OPERATOR: getdata.cxx [line
1199]: DMA read TOFp ADC error

cheers,
-frank

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