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DAE Live View
The DAE, when in event mode, can serve up an AreaDetector image as a live view of the neutron data. This can be viewed using an ImageJ plugin or as an Intensity plot in CSS.
Using the live view device screen you should be able to add a view with the DET macro as 1 or 2
You need to run the DAE in event mode, this will need an event mode wiring table and also defining a second time regime in the time channels section.
Live view PVs have a root at %MYPVPREFIX%DAE:AD1 and %MYPVPREFIX%DAE:AD2 for the two detector case
You first need to tell it the spectra to use for the live view e.g.
caput %MYPVPREFIX%DAE:AD1:INTG:SPEC:START:SP 11
caput %MYPVPREFIX%DAE:AD1:INTG:SPEC:SIZEX:SP 80
caput %MYPVPREFIX%DAE:AD1:INTG:SPEC:SIZEY:SP 80
will tell it to start from spectrum 11 and use consecutive spectra in an 80x80 grid. Setting SPEC:SIZEX sets the underlying area detector SizeX and MaxSizeX. Though SizeX can be smaller, we do binning and size changes etc using a region of interest plugin later so they should always be the same here.
Live view is disabled by default, it is enabled with
caput %MYPVPREFIX%DAE:AD1:INTG:ENABLE:SP 1
depending on the number of spectra, MAX_ARRAY_BYTES may need adjusting
It is possible to use liveview in histogram mode, but this is slower and puts more load on the DAE unless a separate integrating detector card is used (such as on LOQ or SANS2D). Use the parameters to define spectrum numbers etc. as above and then enable this way with:
caput %MYPVPREFIX%DAE:AD1:INTG:SPEC:MODE:SP 1
In this case Y is the spectrum number and X is the time of flight bin.
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SIZEYis the number of spectra in the 1D detector -
SIZEXis (number_of_time_channels + 1) -
SPEC:START:SPis (number_of_time_channels + 1) * (number_of_dae_spectra_to_skip_to_get_to_1D_detector_spectra).
You then need to put the live view into "TOFChannel" rather than "TOFSummed" mode with:
caput %MYPVPREFIX%DAE:AD1:INTG:DATAMODE:SP 1