Ophyd-Async support for DXP detectors #322
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I think we need to consider long-duration measurements such as XRF mappings, where visualizing data on the fly would be great. Not sure whether the HFD reading while writing you mentioned before can resolve this?
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That's something I'd like to have as well. Maybe we should test how SWMR works at the beam line sometime with an area detector?
The DXP IOCs (at least the 4-element vortex) don't seem to have HDF plugins installed though, only netCDF. Not sure how this would be possible with netCDF files. Hoping to figure that out later. It's possible we'll need to add those plugins.
src/haven/devices/detectors/dxp.py
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| def __init__(self, prefix: str, name: str = "") -> None: | ||
| # SNL status records | ||
| self.snl_connected = epics_signal_r(bool, f"{prefix}SNL_Connected") | ||
| # Acquisition control records |
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I vaguely remebered there is also one more option erase_start in epics, but maybe it's not necessary to include this
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Yep, there is.
For the xspress detectors I found that if you start the HDF writer, and then use "erase", you get an extra frame in the HDF file because "erase" sets the ndarray to all zeros and the writer treats that as new data to save.
So to avoid this extra frame, the Xspress device sets "erase", then starts the HDF plugins, then sets "start". I couldn't think of a situation where "start_erase" was necessary, I left it off of the xspress device so people don't accidentally save extra blank frames.
I'm not sure if that extra frame happens on the DXP detectors, though, so if there's a reason to include it we maybe could. Do you have a use case in mind?
| self._drv = driver | ||
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| def get_deadtime(self, exposure: float) -> float: | ||
| # Xspress deadtime handling |
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is this deadtime 0.001 correct, or it's like DXPController above?
maybe we should also add the same comment here
# No-op value. Fill this in when we know what to include
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Good idea. I'll add that to the xspress PR: #316
Things to do before merging: