davidgiven / cowgol

A self-hosted Ada-inspired programming language for very small systems.
BSD 2-Clause "Simplified" License
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Add the OBP assembler and simulator. #118

Closed davidgiven closed 3 years ago

davidgiven commented 3 years ago

This adds assembler and simulator support for the OBP special-purpose computer, used in a variety of spacecraft including the OAO-3 Copernicus orbiting telescope. It's a two's-complement 18-bit word Von Neumann architecture with 50-ish instructions and a surprisingly easy-to-use, orthogonal instruction set. It supports up to 64kw of RAM, divided into 4kw pages, and has hardware multiply and divide, simple memory protection, rich IO including DMA channels, and ran at 250kHz (!).