Next a virtual machine (or interpreter) that has been widespread and used in many computers, even calculators. It started its life running on a processor RCA18021, and systems such as COSMAC VIP from the late 70-ties. Joseph Weisbecker which both invented the physical processor2 and the application of a virtual "processor" CHIP-8, also had a daughter Joyce which is considered as the first female video game programmer/designer.
There is a much larger story here, much to unpack, but we limit the focus to the virtual machine CHIP-8. This implementation here by Dustin Roepsch (among the many thousands there are) of Chip 8 in C, only depends on Ncurses: https://github.com/dustinroepsch/Chip8-curses. Ncurses is a library dating back into the 80-ties, starting as a "clone" of Curses.3 This implies that it can be run in a terminal window with very, very simplified graphics, i.e. text, and also has a nice keyboard connection to C.
This version by Roepsch has the benefit of being rather simple to understand and also few dependencies, i.e. easy to get up and running on many environments.
To get going, after downloading, try:
> mkdir build
> cd build
> cmake ../
> makeIf all went well, you will find in the build/bin the compiled binary of Chip8. Start up:
> ./Chip8 <rom_file>Where you provide your binary sample of a Chip-8 file <rom_file>. You can find some at:
https://github.com/kripod/chip8-roms, or search the web.
Footnotes
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Even before the Intel 4004 (around 1970/1971) Joseph Weisbecker conceived and designed the processor FRED with only discrete logic. Intel is considered to be the first commercial company with a processor to the market. However both RCA and Intel didn't at first understand the importance of this idea what was to become the microprocessor. As a side note the 4004 was first used in Busicom calculators, but the japanese software was adapted through a mechanism close to "virtual machine". ↩
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See: https://en.wikipedia.org/wiki/Curses_(programming_library) and https://en.wikipedia.org/wiki/Ncurses. Also have a look at ANSI escape codes: https://en.wikipedia.org/wiki/ANSI_escape_code. ↩