Field DAQ 101

This document is intended to provide a rough overview of the software components used in the fiel daq and where to find the corresponding code.


In general, all frontends (fe1, fe2, fe3) and the backend have the daq code in: ~/Gm2FieldOnline/gm2fielddaq. This is the part we mainly modify. This builds on top of midas which we have in@ ~/Packages/gm2midas@. Once that's installed and the environment is set up right (through .bashrc calling .midasrc) we hopefully never need to touch that.


The frontend code is in ~Gm2FieldOnline/gm2fielddaq/frontends. They all use the libraries in ~Gm2FieldOnline/gm2fielddaq/hardware-interfaces which only needs to be rebuilt (and INSTALLED) if we make hardware changes what's much less common. The frontends are built inside the corresponding folder. No install is required.

Special case: Fixed-Probes

The fixed probes are kind of special because they need essentially the offline code including the gm2fieldsignal-library for the online freq extraction that is then used in the feedback. This code is in Gm2FieldOnline/srcs/....


Our "midas-server" runs on g2field-be.

Custom Parts

The custom code is located in Gm2FieldOnline/gm2fielddaq/online/custom and the scripts used to start, kill, restart parts including frontends and dqm are in Gm2FieldOnline/gm2fielddaq/online/bin.


To look at the ODB and edit just a few single keys the simplest way is the web interface (mhttpd) -> ODB menu point. To edit larger blocks, restore the ODB, move or copy parts the program odbedit in g2field-be can be used.


The art jobs of the dqm run on g2field-be. The working directory for that is Gm2FieldOnline/DQMWorkplace. The used art modules are in Gm2FieldOnline/srcs/gm2field/dqm while the nodes servers for displaying the dqm are in Gm2FieldOnline/srcs/gm2dqm/node. We run the nodes either on g2field-be or g2field-server-2.

The dqm fcl-files are located at ~/Gm2FieldOnline/fcl, they are copied from the gm2field repository: Gm2FieldOnline/srcs/gm2field/fcl