Midas documentation

Introduction

"MIDAS" is an acronym for Maximum Integrated Data Acquisition System.

It is a general-purpose software package for event-based data acquisition in small and medium scale Physics experiments. Its development has been started at the Paul Scherrer Institute (Switzerland) and at TRIUMF (Canada) in 1993.

MIDAS is based on a modular networking capability and a central database system. It consists of a collection of C, C++ code handling the main functionallity required for data communication between the different acquisition nodes, data control for run operation, data distribution for online data analysis and more. It does also provide the appropriate tools for control and monitoring the run condition from a web application. Midas is supported on current OS such as UNIX-like, Windows, VxWorks. While the system is already in use in many laboratories, the development continues with addition of new features and tools. Recent developments involve multi-threading, FGPA/Linux support, MSCB extension. For the latest status, check the MIDAS home page: Switzerland , Canada

History

In the early '90s, based on a previous DAQ version of a Data Acquisition system running under MS-DOS with network capability (HIX), Dr. Stefan Ritt at Paul Sherrer Institut (Switzerland) started coding a new application which would be OS independent. The requirements at that time were to be able to run on VMS, ULTRIX, VxWorks, Windows. Initial use of Midas has been at Triumf (Vancouver, Canada) for the experimental facility "CHAOS". Network based the data were collected from a VME processor running VxWorks (collecting CAMAC, FastBus & VME data) and sending them to a backend computer (VMS, ULTRIX). Since then, Midas has been deployed on all the major experiments at Triumf and PSI. Midas is used also used around the world in over 80 locations from simple workbench test setups to world class experiments such as MEG (Switzerland), T2K (Japan), Twist (Canada), DANCE (USA).

Documentation organization

Even after two versions of the Midas documentation, it is still a real challenge to describe the Midas package in a clear, concise and useful way. On this third attempt, we reworked the layout and placed everything on Wiki, hoping that collaborators will be keen to correct, add and improve its content. Feel free to do so by contacting us in case of unclear or incomplete information.

We split the documentation in 4 main sections: Installation, Feature listing, Application listing, Online Database. While the first one provide you a mean to get Midas up and running, the 'Feature listing' should highlight what Midas can do and provide some general information on its implementation. The 'Application listing' refers to 'system- & user- build' applications that maybe needed during the acquisition. The 'Online Database' section describes in details the Midas central information database. Appendices as the last section collect references, and features information with the understanding that the reader is already familiar with the Midas environment.

A lot of information can be replicate in every section, but we try to minimize it by cross referencing elements between the different sections. The hope is that once you found the feature that you need, the involved application and the activation of this feature with its online database section will be clear to implement.

• Installation section

While originally Midas was available for all sorts of OS, now-a-days, we tend to reduce its support to Linux based, MacOS, and windows. While 'Midas package retrieval' and 'quick start' sections are OS independent, specific procedure on OS based is given for compilation/build/dependencies. This section also includes the environment variables available for a proper MIDAS-DAQ setup .

• Feature listing

Midas provides you by default a complete DAQ system composed of i.e: Frontend template for acquiring your hardware information, data transfer mechanism to remote computer, data logging capability, data analysis framework, data monitoring, full run control, web interface for experiment control/monitoring. While each of these features is described, other useful option such as subrun, messages, history, etc. may be essential to your experiment.

• Application listing

• Online Database

Installation

Installation & Quick start

Feature listing

Description of Midas features

Application listing

Description and usage of the Midas programs

Online Database

Description of each ODB structure

Appendices

• ===Supported Hardware===
• ===Slow Control Hardware===
• ===Mac specific information===
• ===Multi-threading option===
• ===Event Builder information===
• ===MIDAS Event Structure===
• ===Data Formats===

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