Filesystem (Fs); Cooperation Of The Functional Units - Lacerta M-GEN User Manual

On photos taken without RD some small pattern of the background noise is a typical
effect. This may be caused by the changing gravitational flex in the system (using a guide
scope and a separate imaging telescope) or image movement (rotation) around the guiding star
due to not enough precise polar alignment.
Some effect of using a 'noisy' flat field is also smoothened by RD.
RD works together with the Autoexposure and Autoguiding functions, if enabled. At
disabled state it does not affect any part.

4.4 Filesystem (FS)

As its name shows it is a data storage function of the device. There is 2.088.960 bytes of
free Flash memory for the files' data.
In the filesystem there can be a maximum of 16 file entries. Only one of those can be
opened at a time, which is accessed by all the processes (for data inserting). The open file
stores several types of data –dependent of the parameter settings- to store one or more night's
events to make statistics, search for 'bugs' or just check the accuracy of the autoguiding (or its
parameters). May be used to optimize Your parameters 'offline'.
The files have their own menu, where details can be seen (size, dates, downloaded state),
new file can be created, file deleted, opened or closed. It is advised to download these files to
PC as frequently as possible (with the PC application) to make enough free space for the
forthcoming nights.
There is a date and time settings screen, where the realtime clock (with date) is to be set.
This is essential for timestamping the files' data to a proper identification of the stored data
later. After power-on this screen appears, after then the file menu when You can open a file,
for example the last opened or a new one. (If You skip opening a file, every function will
work but no data will be saved.)
The current version of Firmware stores only one type of data into the open file: if the
Autoguiding is active the guiding star's drift and the calculated correction signal length is
stored. This is the "guiding curve", currently in one huge data stream. (Later versions will
separate these data for each exposures, and the accumulated guiding star image too as a new
feature. Position storing without Autoguiding will give a measurement tool of PE and other.
The PC application will interpret and display these data in HTML format.)

4.5 Cooperation of the functional units

The three main functional parts (AG, RD, AE) need to work synchronized if the RD is
enabled. This communication is shown below in a simple diagram (the time axis goes
downside):
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