First, an introduction. Near the end of July Bernado Kastrup (aka The Byte Attic) put a shout-out on Twitter: A few of my followers suggested I was that man, given my previous experience porting R.T.Russell’s excellent BBC Basic for Z80 to my BSX homebrew and the Spectrum Next. Although the prospect of a shiny new toy to play with was tempting, my projects are backing up, and I would probably not get started on this …
A few months ago at the beginning of the Covid pandemic, after a chance conversation online, a friend from church offered me a Commodore 64 that he’d owned from new. It was untested, and he was happy to donate it for me to play with. I snapped his hand off right away, and a few days later was the proud owner of a Commodore 64. It was the earlier ‘bread-bin’ style, a contemporary design that …
The BBC Micro and Master computers were designed by Acorn from the outset to support a second processor via the proprietary Tube interface. Typically Acorn’s external second processors are in enclosures that matches the aesthetics of the BBC Micro and contain a power supply, processor, RAM and ROM. Essentially a computer without a keyboard and video output. The only IO is via a custom ULA that provides four bi-directional FIFO buffers. The second processors connect …
