Smalltalk-80 on Raspberry Pi: A bare metal implementation
Author here, feel free to ask any questions you have :).It's amazing this little project shows up again here. So far, I received a lot of very positive and friendly feedback about this little pet project of mine.The whole project would not have been possible without the work of Rene Stange, who created the circle bare-metal library for the Raspberry Pi (https://github.com/rsta2) and Dan Banay, who created a C++ implementation of the Smalltalk-80 VM (https://github.com/dbanay/Smalltalk). I mostly hacked together some glue code...If you want to dig deeper, the Blue Book by Adele Goldberg and David Robson (scan provided by Stephane Ducasse, thanks a lot!) is _the_ reference on both the language and the structure and implementation of the underlying bytecode VM: http://stephane.ducasse.free.fr/FreeBooks/BlueBook/Bluebook....Beware, though it's fully functional, crosstalk is still limited by constraints of the original Smalltalk 80 system - e.g. in terms of color (black and white only), possible screen resolution (2^20 pixels, the system crashes if you try to increase the resolution beyond this) and available memory (~1 MB!).Nevertheless, I think it's a rather authentic reproduction of a more than 40 year old system and I learned (in a comment thread on a completely different topic) that one of our fellow hackernews regulars used it to teach his kid Smalltalk programming - love it! I haven't tried to optimize it significantly, so there's no JIT compiler or bitblit acceleration using the Raspberry Pi GPU.There's a more modern bare-metal Smalltalk implementation based on Squeak (https://squeak.org) for the Raspberry Pi by Pablo Marx, though this seems to have some stability problems according to the author: https://github.com/pablomarx/RaspberrySqueakFinally, if you are interested in alternative bare-metal language/OS environments for the Raspberry Pi, you could also give Lukas Hartmann's (of MNT Reform notebook fame) Interim OS a try: http://interim-os.com