ETCa
Extensible Turing Complete Architecture
This repo is for designing an ISA that has a simple base and multiple extensions that can be added on top. Its primary goal is to be easy to build in the game Turing Complete after the second architecture is completed. Several other goals include being educational and being practical for a real CPU.
To get started with the base instruction set, please see base-isa.md.
An extensible assembler built for this ISA is the etca-asm repository in this organization.
Terminology
See RFC-2119 for some of the terminology used in the documentation for ETCa.
Illegal: Specifies that a specific behavior or instruction is NOT allowed in a compliant implementation and must be handled as specified by the ISA.
Reserved: Specifies that the behavior or instruction will be specified in a future extension or feature and should be treated as illegal until it is both specified and implemented.
Unspecified: Specifies that the behavior or instruction is intentionally unconstrained and may be freely handled any way an implementation chooses. Extensions and features can specify or restrict unspecified behavior.