But there are other boards which can do the same. Obviously, the Risk boards were designed to run the FPGA Oberon System.
(Right-click and use a separate window to open this link.) The classic paper by Wirth Tasks vs Threads can be downloaded from this web page. Provides books and articles on operating system architecture. Right-clik on the links and open them in a separate browser window because they may not display in this embedded frame. The articles are available from his Google pages. Dick Pountain published a short introduction to Oberon System and another article on Oberon language in BYTE magazine.You do not need to read Russian to use the website, though basic ability to read Russian will help.
#The oberon system archive
A very comprehensive archive of books and articles is maintained by Oberon Core.The last chapter on the overlapping note design is particularly interesting. It still applies to the 2103 Oberon System despite some minor inconsistencies with the new OS.
The book The Oberon System: User Guide and Programmer's Manual, 1991 is available from the Oberon Core library (see below).Books (Project Oberon, Compiler Construction, Programming in Oberon, and classic Algorithms and Data Structures) can be downloaded from the same website, under the heading "Books".
#The oberon system software
#The oberon system code
Niklaus Wirth and Jürg Gutknecht, Project Oberon: The Design of an Operating System, a Compiler, and a Computer (2013 Edition) discusses both the Verilog source code of the Oberon System On Chip (SOC), and the code of the entire Oberon operating system, including run time, graphics, text editor, and compiler.If it does not (due to recent upgrading of some package, for example), then good luck. You need to follow the clicking cookbook. Basically, there is nothing there that you can understand. Both tutorials will help better understand the difficulty of using the automated Xilinx development toolchain.
A newer version of the same page for Vivado 2018.2 is also available. You can get some flavor of this approach from visiting the Digilent step-by-step Vivado Pmod IP tutorial for Vivado 2015.4.