In 1982, standard computers required dozens of individual chips to handle video, memory management, and peripheral I/O. Sir Clive Sinclair needed to reduce costs and form factor. The solution was the Ferranti ULA, a chip with uncommitted logic gates that could be customized via a final copper routing layer. Core Responsibilities of the ULA
+-----------------------------------------------------------------------+ | PORTABLE RETRO SYSTEM ARCHITECTURE | | | | +--------------------+ Control +--------------------+ | | | Physical Z80 |==================>| FPGA / CPLD | | | | (or CPU Core) | | (ULA Replicating | | | +--------------------+ | Video, I/O, Audio)| | | ^ +----------+---------+ | | | Address / Data Buses | | | v v Screen Data | | +--------------------+ +----------v---------+ | | | SRAM / ROM | | Microcontroller | | | | (Modern Memory) | | / Scan Doubler | | | +--------------------+ +----------+---------+ | | | | | v HDMI / SPI | | +----------v---------+ | | | Portable LCD | | | +--------------------+ | +-----------------------------------------------------------------------+ Step 1: Choose Your Core Architecture You must decide how to implement the CPU and the ULA: In 1982, standard computers required dozens of individual