DAQ

DAQ Software
The Data acquisition software used for this experiment is MIDAS (Multi Instance Data Acquisition System). This software package is developed and maintain at the Daresbury Laboratory (UK), more information could be found at the project web page and should not be confused with the other MIDAS (Maximum Integrated Data Acquisition System) used by PSI and TRIUMF.

The software filled in four different roles,
 * 1) Slow control, allowing for setup of the hardware (setting Discriminator threshold, setting ADC gate,...)
 * 2) Readout of the data from the hardware and writing to file
 * 3) Basic histogramming (one 1D histogram per channel)
 * 4) Online server, making the data available to online analysis.

DAQ Hardware
The entire system in contained in three 19" rack. Rack 1 contained a DELL blade server acting as the main DAQ server (hereafter, the server). The server run the MIDAS software under a Linux Fedora environment. It also act as a DHCP server for all other computer on the local DAQ network. RACK 2 and 3 contain each a VME crate: VME1 and VME2 respectively. VME 1 hold an MVME onboard CPU in slot 1 acting as the crate controller, this CPU is called nnlx1. On startup nnlx1 will first be assigned an IP address by the server, then proceed to download it's kernel via ftp from the server, boot the kernel, and mount the MIDAS software via smtp (therefore nnlx1 os is stored on the server) and finally start the MIDAS DAQ software locally. VME2 is setup as a slave crate to VME1, connected via an SBS 412-1 pair of card, VME2 is therefore seen as an extension to the VME1 bus. The slave SBS 412-1 card located is VME2 act as the VME bus controller of this crate and should therefore fit only in the first slot of the crate.

Starting the DAQ
The first thing to start is the server. For this boot the server and login. User name and password are written on the pull out ID card in the server front panel. Once logged in launch the DAQ startup script:

> ./daq_script/startup.sh

This will first activate all the necessary service for the server to act as such (DHCP, ftp, smtp). This will launch tmux (terminal multiplexer), and split the terminal windows in four. The upper left windows is the minicom output on port com1, connected to nnlx1, it allow you to monitor the status of nnlx1. The upper right windows is the MIDAS64-session windows where the MIDAS DAQ software is executed. The lower left windows is the tape server windows were the "Write to disk" MIDAS software is executed. The lower right windows is left for your use. You can switch form one panel to another by using "ctrl-b" followed by one of the arrow key.