ATLAS Hardware and Software

DoE Visit, 25-OCT-2005
Kevan Hashemi, Brandeis University

Data Acquisition

Data Transport

Production Status

Production of all electronic circuits is complete.

Assembly of all multiplexers is complete

Assembly of all drivers is complete, but logic programming we leave until just before installation.

Assembly of all BCAMs is complete.

Assembly of all proximity masks is 50% complete.

Assembly of all proximity cameras is 50% complete.

Assembly of all azimuthal sources is 50% complete.

Purchase of all cables complete.

Shipping is 50% complete.

Current Work

Set up a 1000-device, multi-VME-crate, test stand at CERN, consisting of eight end-cap alignment sectors, and run this test stand with our LWDAQ (Long-Wire Data Acquisition) hardware and software.

The LWDAQ Software runs well with 100's of devices. We will extend it to 1,000 devices in the test stand, and then to 10,000 devices in ATLAS.

The LWDAQ Hardware runs well with 100's of devices. We will get it working with 1,000 devices in the test stand, and then 10,000 devices in ATLAS.

Software problems we will solve by:

  1. Repeated distribution of new code for Linux, Windows, and MacOS.
  2. Enhancing the LWDAQ's Acquisifier tool.
  3. Enhancing the LWDAQ's System Server for network communications with CERN slow controls.

Hardware problems we will solve by:

  1. Continued development of driver firmware.
  2. Refining the ATLAS data acquisition operating instructions to avoid provoking problems.
  3. Promotion of the LWDAQ support forum.
  4. Expansion of existing documentation.
  5. Development of special devices to overcome errors in installation.

Example Problem

Dirty Power

Dirty 50-Hz power at CERN was causing the DAQ power supplies to fail. Because of a weakness in the hardware power-up reset implementation, these failures caused lasers and LED arrays to turn on.

We modified the driver firmware so that after such failures, the DAQ power supplies turn off.

We added specific power-off instructions to the end of each Acquisifier data acquisition cycle at CERN.

Our colleagues at CERN plugged the DAQ into a cleaner source of power.

We requested and were granted un-interruptable power for our ATLAS DAQ.

Mis-Algined BCAMs

A mis-aligned BCAM in ATLAS will not see its light sources. We are developing two new cameras with wider fields of view that could replace such mis-aligned cameras and allow the system to operate without modifying the mounting plates. One of the new cameras uses a modern CMOS image sensor, and the other uses an larger version of the CCD image sensor we used in our existing cameras.

Slow Data Acquisition

Our existing TCP-VME Interface may be too slow to support image transport out of the ATLAS detector hall. If it is too slow, we will design and build a faster version for our five VME crates.

Other ATLAS Work

We are developing a Inclinometer (also known as a tilt sensor) for use in aligning the end-cap sectors. (For application questions, ask Hermann.)

We have developed a gas Flowmeter, whose performance we have studied in detail, for use in the ATLAS argon supply. (For application questions, ask Hermann.)


ATLAS production is almost complete.

We will work on some new designs to help us overcome errors in installation.

We will continue to expand our software.

Our hardware and software is reliable on systems containing 100 devices.

We will get it working reliably on a 1000-device test stand.

After that, we will get it working in the 10000-device ATLAS system.