Two modern demos for Acorn’s BBC Master 128k have been written up by their authors in considerable detail over on stardot:
Acorn’s Master benefits from a 2MHz CPU, and has reasonable resolution, but only 4 bits per pixel - black, white, and 6 garish colours - and no sprite engine. Also a weak sound chip. So it’s quite a challenging machine for demos. Unlike the Beeb original, it has heaps of RAM, but in a rather interesting memory map. The CPU is a 65SC12, rather like a 65C02.
The two demos can be seen online: