AGATA Digitizer Slow Control

Introduction

The AGATA Digitizer Slow Control is a component of the global slow control for AGATA. It therefore implements the AGATA Slow Control SOAP procedures in addition to providing access to enable configuration and diagnostics to be carried out by system adminisrators and systems engineers.

The AGATA Digitizer hardware has an embedded ethernet interface which permits connection to an ethernet segment. However the commercial interface device using (Lantronix Xport) has limited firmware which permits only a single network connection (TCP) stream. Additionally the FPGA which controls the ethernet interface also has limited resources available. It is hence not possible to implement the AGATA Slow Control protocols within the Digitizer modules themselves.

For this reason a Linux based workstation acts as a gateway between the rest of the AGATA system and the Digitizer modules. The AGATA Digitizer Slow Control software runs wihin this workstation and communicates over a private ethernet segment using private protocols with the firmware running in the Digitizer hardware. No direct access is possible to the Digitizer hardware.

You can view this diagram at full resolution here.

Operation

In normal production use the Digitizer Control will be via the Global AGATA Control system. There are relatively few settings within the digitizer which need to be adjusted on a per experiment basis. Once the digitizer modules have been configured a single command via the AGATA Slow Control can be used to SETUP all digitizers and they are then ready to acquire data.

Graphical User Interface

The AGATA Digitizer Slow Control includes a Web interface which can be accessed from any standard Web Browser which has JavaScript enabled. No further software needs to be installed in the client system.

The GUI provides the following features

  • Setup of one or all digitizer modules      See screen dump
  • Setup of the software offsets      See screen dump
  • Control of the Core module Preamp Pulser      See screen dump
  • Diagnostic access to the registers controlling data flow between the digitizer module and the front end readout electronics      See screen dump
  • Monitoring of the termperature sensors within the digitizer modules      See screen dump
  • Low level diagnostic access to the internal registers of the digitizer modules      See screen dump
  • Configuration of the gateway software      See screen dump
Screen snapshots taken Sept 9 2008 with updates Feb 17 2009

Implementation

The network protocol used by the AGATA Digitizer Slow Control is based on the Simple Object Access Protocol (SOAP) which is the foundation layer of the web services protocol stack. The web service is described by its Web Services Description Language (WSDL) definition file. The WSDL file for the AGATA Digitizer Slow Control is here.
Additionally the AGATA Slow Control protocol is implemented which is also a Web Service and is defined by a WSDL file which is available here.

For further information on the software implementation see Implementation of XML/SOAP client and server facilities within MIDAS and MIDAS Web Services Implementation Guide.

Elog

The Slow Control pages are linked to the AGATA Elog. See here for details of the Elog package. Some information is entered into the Elog automatically while the contents of the Slow Control Log Windows can be sent to the Elog at any time. Here are two sample screen dumps of the Elog. 1 2

Software

The software for the AGATA Digitizer Slow Control is available here. This is a complete archive of all required software components. Last Updated 17 Jul 2014.

 Xport Communications Package This is the code used by the AGATA Digitizer Slow Control plugin Web Service to access the Digitizer Xport Interface (265Kbytes). It contains the code, build directories and various test programs for Linux, Solaris and Windows (Last Updated June 14 2009)

 Xport Configuration Package This is the Windows based software package for configuration of the Xport interfaces (3.2 Mbytes). It can be used to set the IP address if a digitizer is moved.

 Spartan command protocol This is the communications protocol used between the control software and the Xport (Spartan)

V Pucknell; STFC; Daresbury Lab   Last Updated 17 July 2014