Low level data fields - ComPair/ComPair-tracker-FPGA GitHub Wiki

L0/L1 Data Fields and Definitions

Todo:

  • Add event type information.

Definitions:

  • "digital threshold" : Zero-suppression threshold. Defined in ADC count space; can be defined as a set level (400 a.d.c. counts) or as a level above the common-mode value of all channels (i.e. 100 a.d.c. counts above the ASIC average). This is usually turned off.

Attributes

  • n_asic : number of ASICs in the dataset. Should be 12 unless we're doing something weird.
  • n_packet : number of data frames in the dataset.
  • config : ASIC configuration information not yet implemented
  • layer_id : some layer identification information (e.g. fpga hostname) not yet implemented
  • run_info: Text field for keeping run notes not yet implemented. (e.g. is this a calibration run, is this

Groups

The hdf5 files generated from the raw binary files are organized with the ASICs in "groups" and each ASIC has the following fields:

  • channel_status : 1 if there is a digital trigger on the channel, 0 if none.
  • chip_data_bits : 1 if there are any ADC values in the ASIC above the digital threshold.
  • cm_data : Data from the common mode (think of it as an average of all channels).
  • cm_status : Common-mode status bit; always 1.
  • data : ASIC data
  • dummy_data : Data from the dummy channel. Use for tracking ASIC-level variations due to (e.g.) temperature.
  • dummy_status : Status bit for the dummy channel. Always 1. Do not use.
  • event_id : 32-bit event number set by the trigger module. Zero's if trigger module is not present.
  • event_number : 32-bit event number determined by the ASIC
  • live_time : 64-bit counter corresponding to when the ASIC is not in IDLE mode.
  • running_time : 64-bit free-running counter corresponding to how long the system has been running.
  • seu_bits : 1 if an SEU occurred
  • start_bits : 1 always if the ASIC provided ANY data.
  • stop_bits : 1 always if the ASIC provided ANY data.
  • trigger_bits : List of 32 bits; 1 if there is a digital trigger in the channel, 0 otherwise.
  • trigger_status : Was a trigger generated by this ASIC for a given event.