A developer known as Leaded Solder is running Tetris on the BBC Bridge Companion, a 1985 British TV-connected bridge tutoring console that sold for £200 and moved few units. The machine runs a Z80 processor with a TI video chip and 16K of VRAM, the PAL variant, which made it capable hardware for its era despite its narrow purpose.
Getting code to run was not straightforward. The Bridge Companion executes its own bootstrap before loading any ROM cartridge, so Leaded Solder spent several evenings reverse engineering the correct header format. The physical hardware also needed cartridge slot repairs before real testing could begin, and PAL output required adaptation to work with a composite monitor.
This is a two-part series so far, with more posts expected before the end of August. The second installment covers the cartridge build and repair in technical detail. Read both parts if you want to understand what it actually takes to homebrew on hardware that was never meant to run anything except nine official bridge cartridges.
[READ ORIGINAL →]