Karabas-Nano

Yet another ZX Spectrum clone ;)

Intro

ZX Spectrum compatible machine with real Z80 CPU and all logic inside the CPLD Altera EPM3256ATC144 (or EPM7512).

The idea

The idea was to learn KiCAD and make a cheapest and smallest ZX Spectrum clone with minimum components and real CPU. Some parts of this schematics are grabbed from the Karabas-128 and ZX-UNO projects (like RGB DAC, PAL coder, Tape-in logic). The heart of this project is a real SMD Z80 CPU and ULA implementation on Altera CPLD EPM3256ATC144.

Firmwares

The board contains an SD card socket, so at least 2 different configurations are supported:

1. Z-Controller based configuration (Pentagon timings, GLUK reset service in the ROM bank 0, 1024kB of extended memory via port #DFFD (Profi))

2. DivMMC based configuration (Pentagon timings, ESXDOS 0.8.7 in the ROM bank 0, 128kB of memory)

More info

ERRATA for PCB rev.A: Russian.

ERRATA for PCB rev.B: Russian.

Latest revision: rev.I.

License for this project is WTFPL. More details here.

Pre-production renders

PCB Rev. H assembly example by Xoomoh (Михайло Капітанов)