The ZX Spectrum is an 8-bit personal home computer developed by Sinclair Research. It was first released in the United Kingdom on 23 April 1982 and went on to become Britain's best-selling microcomputer (https://en.wikipedia.org/wiki/ZX_Spectrum)

This project is the clone of ZX Spectrum 128, made from Standard Logic Gate ICs instead of Custom IC (ULA: Uncommitted Logic Array) as in original ZX Spectrum and has many advance than original.

Specification

- PCB rev 3H support 128K, 128K+2, 128K +2A/+3/+3E ROM

- EPROM 29F040/39SF040 (upto 8 banks of 64K, select by dip switch)

- 128K RAM

- Video signal is ZX Spectrum 48K/128K timing (select by switch)

- AY-3-8910 sound chip

- Simple 8 bit IDE interface on board (for use with HD/CF and +3e ROM)

- Support external +3 FDD controller

- RS232 on board

- RGB and Composite output, support both PAL and NTSC (There is a footprint to install 3.579MHz oscilator for NTSC)

- Use standard ZX Spectrum Adapter, 9V with center pin negative (-)