# DAQ / Replay controls

Fig. 13 DAQ controls

The effects of the buttons depend on the current mode - DAQ or replay - and the current state of the system:

Table 1 DAQ control actions
Action | DAQ mode | Replay mode
--- | --- | ---
Start | Run DAQ startup procedure Open new listfile | Start replay from beginning of file
Stop | Run DAQ stop procedure Close listfile | Stop and rewind to beginning of file
Pause | Leave DAQ mode No special procedures are run | Pause replay

The Start button allows to choose what should happen with existing histogram data. Selecting Clear will clear all histograms in the current analysis before accumulating new data. Using Keep allows to accumulate the data from multiple replays or DAQ runs into the same histograms.

The Reconnect button will attempt to reconnect to the current VME controller.

If Write Listfile is checked a new output listfile will be created when starting a DAQ run. The file will be created in the listfiles subdirectory of the current workspace. The filename is based off the current timestamp to make it unique.

Use the Compression drop down to switch between a fast compression mode (ZIP level 1) and no compression at all (ZIP level 0). Even without compression the raw readout data is still placed in a ZIP archive together with the analysis and log buffer contents.

Note: testing showed that higher compression levels did not yield a significant increase in data reduction but had a high performance impact so the higher level modes are not currently selectable via the GUI.

Use the Run Settings button to change settings regarding the naming scheme of the listfiles produced during DAQ runs.

The Workspace Settings dialog allows setting the experiment name (used by the ‘Event Server’ component) and enabling/disabling the JSON-RPC and Event Server components.

## Replaying data from listfiles

To replay data from a single listfile use File -> Open listfile and choose a .zip or .mvmelst file.

When opening a listfile the VME config included inside the file is loaded and will replace the current config. The global mode will be switched to Listfile. To go back to DAQ mode use File -> Close Listfile.

There is also a dedicated ‘Listfile Browser’ window which can be opened via `Window -> Listfile Browser (Ctrl+4)`. In addition to replaying from single files the listfile browser allows to replay data from split listfiles (ending in `partNNN.zip`). Make sure `replay all parts` is checked before opening the first part of a split listfile, then start the replay normally. The partial listfile archive currently being read is printed to the log window. To the analysis it looks like the data stream is coming from a single file.