Rocketlogger

The changes since version [1.1.6](version-116-2019-07-31) include all changes of the the beta release [2.0.0-beta1](version-200-beta1-2021-06-12) and the fixes and improvements listed below.

Base operating system:

Base operating system:
* [ADDED] local operating system image patching to generate ready to use RocketLogger image (4)
* [ADDED] switch to Debian *buster* release (2)
* [CHANGED] install operating system to BeagleBone's embedded eMMC memory, use external SD card for configuration and data storage
* [CHANGED] simplify remote system setup procedure

RocketLogger software:
* [ADDED] use meson build framework for combined build and installation of all software components
* [ADDED] PRU measured ADC sample interval, available as optional `DT` channel (17)
* [ADDED] switch to ZeroMQ messaging library for data streaming to the webserver
* [ADDED] Node.js based web interface with server side data streaming capability (3, 5, 9)
* [CHANGED] command line interface update: improved argument consistency and more robust argument parsing _(backward incompatible)_
* [CHANGED] rework low level hardware interfacing for Debian *buster* compatibility (2)
* [CHANGED] update and reorganize internal software API and headers for increased consistency
* [CHANGED] update to latest and official compiler tools (18)
* [CHANGED] Binary file format: increment file version to `0x04`
* [REMOVED] legacy web control interface

Python support library:
* [ADDED] extended get data API to access relevant header fields and filenames, add pandas DataFrame generation
* [ADDED] add header-only import, recovery mode for truncated file import
* [ADDED] add calibration support (10)
* [ADDED] sample data processing and calibration scripts (7)
* [CHANGED] make plotting an optional feature to reduce package dependencies
* [CHANGED] `get_time()` API: use `time_reference` for timestamp reference selection (using updated parameters!), drop `absolute_time` argument _(backward incompatible)_
* [FIXED] deprecated NumPy API dependency (12)

MATLAB support:
* [DEPRECATED] The MATLAB support for processing RocketLogger data is deprecated and will be removed in a future release. It is recommended to switch to the more feature-rich Python support library (11)
* [REMOVED] The MATLAB calibration support has been dropped. Use the Python support library to generate new or convert existing calibration data


_Notes:_

This beta release for the next major version updates the base operating system to run the latest Debian version and includes numerous internal software and development tool changes. The most noticeable change for the user is the new web control interface that was implemented from scratch.
Calibration features were added to the Python support library and the data processing functionality was extended.

Due to the major upgrade of the base operating system from Debian version 7 to 10, and the change of the install location to the internal eMMC memory, the RocketLogger system needs to be reinstalled.


_Known Issues:_

* Unresponsive web interface when system partition is running out of space (23)
* Startup artifacts after RocketLogger system startup or hardware reset (19)
* Python library uses target instead of theoretical configured sample rate for relative timestamp calculation (13)

* [FIXED] Software: potential corruption of ambient file name (127)
* [FIXED] Software: typo in ambient file channel name (128)
* [FIXED] Software: wrong scale for default file split value (124)
* [CHANGED] Python support: document successfully tested compatibility with recent Python and NumPy releases

_Notes:_

This hotfix release addresses two issues related to storing ambient sensor data and an invalid default value in the measurement file split configuration. The Python support package was tested to successfully work with recent Python and NumPy updates.

* [FIXED] Software: corrupt data when writing files >2 GB (119)
* [FIXED] Software/web interface: data aggregation issue for larger time scales (117)
* [FIXED] Documentation: more detailed description of common measurement setups and user interfaces (114, 120)
* [CHANGED] Software: split data files at 1 GB by default (relates to 119)

_Notes:_

This hotfix release resolves a file writing issue when saving the measurements to a single large data file and a data aggregation issue in the web interface preview. Furthermore, the documentation in the wiki on measurement setup and control has been updated and extended.

* [FIXED] Software: corrupt data when using high sampling rates and values are close to full range (116)
* [FIXED] Python support: single data block file import issue (115).

_Notes:_

This hotfix release resolves a data wrap-around issue for sampling rates of 32 kSps and 64 kSps and a Python support bug when importing files with a single data block.

* [FIXED] Software: corrupt low current valid channel when digital channels are disabled (108)
* [FIXED] Software: invalid lux calculation for mid/high range of TSL4531 (111)
* [FIXED] Software/web interface: add more detailed version information (112)
* [FIXED] Software: invalid data block timestamps in sensor file (113) by [masoudinejad](https://github.com/masoudinejad)

_Notes:_

This hotfix release resolves an issue with the low current valid channel when disabling digital channels and two bugs related to logging external sensors.
The software now includes the git revision and build date in its version information output.