ZX Spectrum, Expansion Port Research

This video builds on the work I did looking at the rom cartridge port on the spectrum by taking a wider look at the main expansion port. Most of the time is spent exploring the additional control signals that deal with memory and IO access.
We round the video of with a partial interface of the UART I built for my homebrew cpu.
0:00 Introduction
0:36 Discussion
2:10 Breakout Design
7:45 Unbox and Soldering
12:56 Signal Exploration
22:51 Capturing Memory Write
28:58 Uart Interfacing
38:46 Outro