z80 Single Board Computer

z80 Single Board Computer based on "Grant's 7-chip Z80 computer".

Modifications from the original include:

- a 16550 UART to replace the 6850

- added a 8255 PPI parallel interface to allow controlling of external projects

- some modifications to address control logic

Software is adapted (GIT repository) accordingly and assembled on a Linux machine using the z88dk toolchain. This is a SmallC+ and Z80 assembler cross-compiler supplied with an assembler/linker and a set of libraries implementing the C standard library for a number of different z80 based machines.

Project pics and progress

November 1, 2014

[mostly] wired board with running BASIC interpreter. The latest circuit diagram with some corrections.