FADC Data Format February 10, 2015

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Revision as of 16:49, 10 February 2015 by Nsjarvis (Talk | contribs) (Minutes)

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Location and Time

Room: CC L207

Time: 2pm.

Remote Connection

(if problems, call phone in conference room: 757-269-6460 might not be the correct number)

  1. To join via Polycom room system go to the IP Address: 199.48.152.152 (bjn.vc) and enter the meeting ID: 589693655.
  2. To join via a Web Browser, go to the page [1] https://bluejeans.com/589693655.
  3. To join via phone, use one of the following numbers and the Conference ID: 589693655
    • US or Canada: +1 408 740 7256 or
    • US or Canada: +1 888 240 2560

More information on connecting to bluejeans is here

Specific instructions for connecting via polycom:

  • Turn polycom on if necessary
  • With the polycom, place a call at 199.48.152.152
  • Press # to enable the polycom keypad, then enter the meeting id: 589693655 and #
  • You may have to unmute the microphone: #*4
  • Turn the computer on if needed

Agenda


Useful Links

Minutes

Present: Naomi (CMU), Cody, Beni, Sergey (JLab)

  1. Cody has been testing the firmware with a pulser to find the maximum trigger rate before the firmware runs into trouble. The problems are in multiblock mode (this is with more than 1 event per block) when two triggers occur too close together, the fadc is not ready to be read out, it gives a block error but the buffer is not emptied, the next event reads out the old data in the buffer from then on the events are out of sync and the whole block has to be discarded.
  2. He has found that in mode 8, with 200 samples, the firmware is good at rates up to 5kHz, and with mode 7, 200 samples, it is good for rates up to 34 kHz. This was with NSA=2, NSB=15. Next he will try NSA=5, NSB=60.
  3. David has ported the new firmware timing algorithm into the analysis library. Naomi will try it out.
  4. Naomi suggested giving the new firmware's time module a time limit - we know the max number of clock cycles that it should use, if it takes more than this then something is wrong. She has not found any example pulses which would cause this.
  5. We talked about the error conditions returned by the time module, including some rare conditions caused by faulty fADCs.