Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 1

Online & Calibration/Monitoring

November 11, 1998

Calibration and Monitoring - Online Needs

Glenn R. Young

ORNLORNL

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 2

Online & Calibration/Monitoring

November 11, 1998

“Lies, Damned Lies, & Electronics”

apologies to M. Twain

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 3

Online & Calibration/Monitoring

November 11, 1998

Things You Need to Prepare

Mappings» Where is channel #i on FEM #j in Sector #k?

Calibrations» Energy equivalent per ADC count» Time equivalent per ADC count» Time-0

Monitoring» Gain variation» Channel health» Timescales (hourly, diurnal, “aging” in 10 years)

All this “stuff” stores in a database

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 4

Online & Calibration/Monitoring

November 11, 1998

Mappings

Electrodes hooked to FEM cards Which FEM cards in each Sector For one FEM card:

» Production serial number» Platform/Rack/Crate as applicable» Low Voltage supply» High Voltage supply (?)» Timing Fiber input» DCM Fiber output (“routing” FEM?)» Trigger Fiber output, if applicable» ARCnet node ID, subnet ID

Bad Channel Maps Pulser Masking

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 5

Online & Calibration/Monitoring

November 11, 1998

Calibration

Gain Calibration» electrode/amplifier/digitizer» AMU or TMU cell» DAC-to-energy/time» Thresholds in useful units (mips)» Trigger connection, thresholds

Time Calibration» See above, plus stepping of timing markers» sampling times, (bandwidth limiters)

Digitizer INL, DNL» How wide is a given channel in MeV or ns?

Plateau, Efficiency Determination Trigger Settings

» Thresholds, cut limits» Road widths» Multiplicities

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 6

Online & Calibration/Monitoring

November 11, 1998

Monitoring

Pedestal centroids, RMS values Gain drifts Time-zero drifts Channel health Efficiency changes Resolution variations

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 7

Online & Calibration/Monitoring

November 11, 1998

A Partial Example - EMCal

Basic idea is familiar» configure everything» fire some signal input» tell the trigger to take this event» write a lot of stuff into databases» change some variable(s)» repeat N times» analyze the results, decide what you did wrong, repeat

until correct....

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 8

Online & Calibration/Monitoring

November 11, 1998

What is Available to Work With?

PbSc: laser, PMT-side LED PbGl: 3 LED types on front Maskable calibration pulser - energy Maskable calibration pulser - timing Analog mux (geeks only) Various mask registers

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 9

Online & Calibration/Monitoring

November 11, 1998

What is to be Determined?

R U There? Pedestal centroid and rms values Energy calibration

» Light-injection as long-term reference» Cosmic rays (or beam muons) for scale

Relative gain calibration: x1 vs. x16 Timing channel calibrations AMU Cell-Dependences, if any Timing discriminator threshold Cosmic muon, trigger thresholds Relative timing to RHIC clock

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 10

Online & Calibration/Monitoring

November 11, 1998

What has to be Setup, Downloaded?

LV, HV assumed “on”, within limits ARCnet has to be awake (else kaputt) FPGAs downloaded Glink Rx (timing) locked Glink Tx (data, trigger) locked Serial downloads performed

» AMU Cell offsets chosen, ADC setup» Variable Gain Amp: gain and bandwidth limit» Discriminator DAC settings, TAC Range» Pulser DAC settings» Trigger threshold DAC settings» Channel masks set (pulser, hook-to-trigger)» Any “enable” bits» Mux-select, if scope-probing today» Any board-ID that is configurable

Programmable Pulse Generator Setup

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 11

Online & Calibration/Monitoring

November 11, 1998

Choose Independent Variable, Reps

HV? DAC value? Channel mask? External light/charge source?

Pick a number of repetitions» (perhaps nest loops?)

Decide what, if anything, goes into your “User Words” written to DCM

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 12

Online & Calibration/Monitoring

November 11, 1998

Set Up The Scheduler

“Scheduler” - a Granule Timing Module function

You have three sets of Mode Bits» FEM Mode Bits

– initialize, run, fire on-board pulser

» LVL-1 Mode Bits– tell LVL-1 to force an accept of correct crossing– tell LVL-2 not to reject this event in ATPs

» PPG Mode bits– fire external stimuli at chosen time delay– light injected into PbSc, PbGl, RICH, TOF, BB– charge injected into MuTR anode wires

You have to Time-(mis)Align the Mode Bits» when you fire the laser and/or pulser» when you fire the LVL-1 trigger» when you reset charge-integrators» how long these things last (if >1 tick)

Note: PPG has time-vernier for its outputs

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 13

Online & Calibration/Monitoring

November 11, 1998

Run Control

Now things are prepared Take N events End Run (?) Change HV or DAC or laser or ... Re-initialize, if needed

» e.g. re-load of serial strings likely» re-load of FPGA if parameters stored there» very likely need to re-start Scheduler

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 14

Online & Calibration/Monitoring

November 11, 1998

Some Proceedures I’d Like to Have

Method to step thru N High Voltages» “equally spaced”» pick start HV, step size, number of shots» take data, extract centroids and RMS values» store in “spreadsheet”

– index by channel #, HV value, signal source/value

» fit peak position vs. HV, extract gain coefficients, put those in database

» choose future HV settings using this info

Method to step thru N DAC settings Method to step thru N t0 settings Method to step thru N channel masks Method to step thru N pulser settings Method to step thru all LVL-1 Mux-n-

Mask settings

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 15

Online & Calibration/Monitoring

November 11, 1998

More Proceedures I’d Like to Have

Method to slew HV for plateau, efficiency determination

Method to use HV vs. gain info» select HV, download it» fire (properly configured) pulser N times» check centroids and RMS values» tweak “near-outlying” channels» report misbehaving channels» blacklist dead channels

Method to check trigger uniformity Method to check trigger response

» set up pattern of pulse-heights/# strips/fired roads» used Forced Accept to take event, no matter what LVL-1

decision is» compare expected to actual behavior» adjust LVL-1 cuts if needs be» fix an errors found, e.g. in road indices

Glenn R. Young, ORNL 04/21/23 BNL Core Week Computing Meeting 16

Online & Calibration/Monitoring

November 11, 1998

Some Tools Needed

Ability to pull raw data “all the way up” to analysis workstations» DCM in pass-thru mode» You can pad bits, add header/trailer, but DO NOT mess with the

FEM’s basic payload

Histogramming, peak fitting» Running sums, means, rms?

Much of “tuneup” can» write to disk,analyze, examine, tune parameters» discard “last data” and re-start/repeat

Store and query in “database”» “Best”place to store pedestals may be (only?) in DCM memory

Over-ride of LVL-1 decision (Forced Accept) Way to move events by 1-few “ticks” in

Scheduler Write/Readback/Compare/Alarm-on-Non-Match

of Serial via ARCnet