[Halld-level1] Data stream scalers, summary of the meeting

[Alexander Somov]

Hi,

I brief summary of the data stream scaler
implementation  discussion last Friday
(Jan 20th, 2012):

1. Scalers will be integrated into the data readout
block of each FADC; they will be readout using DMA.

2. There are two ways of the implementation:
   a) scalers will be added to the last event in
      the block. A user needs to specify the block
      prescaling factor, i.e., the number of blocks
      after which the scalers should be added
      (for instance, add scalers in each 10000's readout
      blocks).
   b) Scaler readout will be handled by the special
      trigger type generated by the TS (the trig2 line
      going from the TI to the fadc can, for instance, be
      used for the scaler trigger distribution). Similar
      to a), scalers will be added to the readout block.
      Implementing this mode will require more efforts.

3. Edd and Bryan will start implementing mode a).


Cheers,
       Alex