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README.md

+# Vienna Flight OS
+
+This is a development snapshot of the Vienna Flight OS intended for future use
+in software contributions by the
+[space instrumentation working group](https://www.univie.ac.at/space/gtknodes/index.html)
+at the Department of Astrophysics of the University of Vienna.
+
+The current focus is on LEON3/LEON4 SPARC processors, but ports to different
+architectures (such as RISC-V) may be added in the future if required for our
+purposes.
+
+## A Brief History
+
+This is a development which has its roots in an evaluation study
+of the MPPB (Massively Parallel Processor Breadboarding) prototype hardware
+and was later expanded to target the SSDP (Scalable Sensor Data Processor),
+which was intended to become a next-generation space-rated
+system-on-chip that included Xentium DSPs in a Network-On-Chip which were
+to be controlled by a general-purpose LEON3 host CPU.
+
+While the SSDP has been abandoned, the extensions needed to operate the NoC and
+the DSPs were never more than modular components (and are in fact still part
+of the source tree) of the operating system so its development is continued.
+
+Please note that this was originally referred to as *LeanOS* as a working title,
+but since the name was not very descriptive of its intended purpose, it was
+recently changed to *Vienna Flight OS*. References in pre-rendered versions of
+the PDF documentation are thus still referring to LeanOS.
+
+# Documentation
+
+See Documentation/ subdirectory.
+
+
+## Build instructions
+
+(extremely brief, will expand later)
+
+### Prerequisites
+
+- bcc or bcc2 (preferred) tool chain
+- GR712 or GR740 develpment board
+- grmon
+
+### Building
+
+The build system is based on a modified variant of *kbuild* as used with
+the Linux kernel, so you can configure the build with *make menuconfig*.
+
+To run the copy performance/ threaded multicore demonstrator, copy
+gr712_demo-config or gr740_demo-config to .config, then run *make*.
+
+You may need to change the cross-compiler prefix for your particular tool chain
+(default is *sparc-gaisler-elf-*). This can be achieved by editing the .config
+file or by running *make menuconfig* and in the *General Setup* submenu.
+
+If you run into issues with cpu-specific compiler flags, you may want to
+have a look at *arch/sparc/Makefile* and change the options accordingly.
+
+
+# References
+
+For an overview of the development history (in order), see:
+
+<https://indico.esa.int/event/60/contributions/2757/attachments/2284/2639/DSP_Day_2014_-_NGAPP_final_presentation__RUAG-A.pdf>
+
+<https://indico.esa.int/event/102/contributions/39/attachments/152/177/5_2_P_A_Lightweight_Operating_System_for_the_SSDP_20160613.pdf>
+
+<https://indico.esa.int/event/182/contributions/1513/attachments/1430/1655/1220_-_Luntzer.pdf>
+
+<http://microelectronics.esa.int/userday-gr740/16_10-Armin_Luntzer_gr740userday2019.pdf>
+