EightThirtyTwo is an experimental CPU core with 8-bit instruction words and 32-bit registers.<\/p>\n\n\n\n
The main design goals are modest logic footprint and minimum possible use\nof BlockRAM – which is achieved by (a) aiming to maximise code density,\nand (b) having the register file implemented as logic rather than BlockRAM.<\/p>\n\n\n\n
In order to maximise code density, the instruction words are only 1-byte\nlong, with only three bits devoted to the operand. This allows one of\neight general purpose registers to be selected, while a ninth “tmp” register\nprovides an implicit second operand.<\/p>\n\n\n\n
There is optional support for dual threads, and the CPU offers full load\/store alignment, build-time switchable endian-ness and 32 x 32 to 64 bit multiplication.<\/p>\n\n\n\n
The project is hosted on GitHub in two parts:<\/p>\n\n\n\n
I have blogged about the creation of this CPU, so for those interested in reading about the process, this page serves as a sort of index.<\/p>\n\n\n\n
EightThirtyTwo is an experimental CPU core with 8-bit instruction words and 32-bit registers. The main design goals are modest logic footprint and minimum possible use of BlockRAM – which is achieved by (a) aiming to maximise code density, and (b) … Continue reading