BBC Micro MOS layer → Neo6502 API (OSWRCH, OSBYTE, OSWORD, OSCLI…). Epic 3: the reload BBC emulator boots MOS 1.20, BASIC 2, DFS, and starts Spellbinder.
Status In progress
The BBC Micro and the Neo6502 share the 6502; BBC games call the MOS through fixed vectors at $FFxx, easy to repatch. Neo6502bbc redirects OSWRCH, OSBYTE, OSWORD, OSCLI, OSRDCH, OSFIND and OSGBPB to the firmware API. Epic 3 in progress: a BBC Model B emulator (reload, bbc branch) boots MOS 1.20, BASIC 2 and DFS on the PC and takes Spellbinder to its first playable room. The Neo6502 does better than the Oric for these ports: native 320 pixels, MODE 5 in 4 exact colours.
Source code not published yet.
The Neo6502 (W65C02S + RP2040, firmware by Paul Robson) as seen by Tachibana: Phosphoneo, Neo6502kbd, Neo6502bbc, firmware fork, AsteroNeo, Neo6502Prophet, framing — now tested on a real board. Read the article →