Digital BCM Meeting, 2021 March 24

From Moller Wiki
Jump to: navigation, search

Back to Main Page >> Data Acquisition Meetings

previous meeting << >> next meeting

Meeting information

 Meeting time:  4:00pm Eastern
 
 We'll be using this LBNL zoom link for the meeting:  https://lbnl.zoom.us/j/95645100291

Agenda

  • Discussion of options and tradeoffs of how TI connection is made to the VCU108
  • General discussion

Minutes

Participants: R. Michaels, B. Moffit, W. Gu, S. Li, E. Sichtermann, Y. Kolomensky, Y. Mei, A. Cuda

  • Discussing how to make the TI connection
    • William and Yuan discuss the TI_FMC schematic. William thinks the trigger signal will be what carries the start of the helicity gate
    • In the CODA system, the sync/reset is used to zero the clock counter. This is how the timestamps are generated.
    • The four lines on the QSFP are:
      • RX/TX1: Trigger; 1.25GHz
      • RX/TX2: Clock; 250 MHz
      • RX/TX3: Sync; 250 MHz, Manchester encoded
      • RX/TX4: Fiber loopback; 250 MHz, Manchester encoded. This is used to measure the cable length, but we could do without it by measuring the cable connection by hand.
    • The GPIO connector on the VCU108 ought to be able to handle the 250 MHz signals, but couldn't support the 1.25GHz trigger signal.
    • The "Samtec Bullseye" connector on the VCU108 can handle the 1.25GHz signal
  • New development plan
    • Yuan will develop an interface board which will connect to the Bullseye and the GPIO connectors, and this would then be able to support all TI functionality
    • Since the TI QSFP connection will be done on the new interface board, we would have the option of using the VCU108 QSFP for the data connection