Precise JavaScript emulation of Intel 8080 CPU
Based on BSD-licensed work by Copyright (C) 2008 Chris Double
All flags and instructions fixed to provide perfect compatibility with original "silicon" CPU.
This emulator passes the Exerciser https://www.idb.me.uk/sunhillow/8080.html
Big thanks to Roman Borik (https://pmd85.borik.net). His help lets me achieve such a perfect HW compatibility.
Used in all emulations at ASM80 online IDE
(a.k.a. The API)
- window.CPU8080 - main object (instantiated at the start - it shall change)
- CPU8080.init(memoryTo,memoryAt,ticker,portTo,portAt) - Initializes the whole system. All parameters are callback functions for port / memory access:
- memoryTo(addr,value) - store byte to given address
- memoryAt(addr) - read byte from given address
- ticker(T) - unused. For future use
- portTo(addr,value) - write byte to given port
- portAt(addr) - read byte from given port
- CPU8080.T() - returns clock ticks count from last init (or reset)
- CPU8080.reset() - does a CPU reset
- CPU8080.set(register, value) - sets internal register (named PC, A, B, C, D, E, H, L, F, SP) to a given value
- CPU8080.status() - Returns a object {pc, a, b, c, d, e, h, l, f, sp} with actual state of internal registers
- CPU8080.steps(N) - Execute instructions as real CPU, which takes "no less than N" clock ticks.
Disassembler:
- window.CPUD8080 - main disassembler object (instantiated at the start - it shall change)
- CPUD8080.disasm(i,a,b) - Disassembly instruction. You have to provide 3 bytes - first one is an instruction code, second and third are parameters (they can be omitted when instruction is single byte or two bytes). It returns an array of two elements: the first is instruction mnemonics, the second is an instruction length.
You can use 8080js also as Node.js module.
8080js is slightly tested with qUnit - just a basic functionality at this moment
Use emu8080test.html for testing with a real test suite
- Change it from self-called constructor to real class
- Prepare exerciser as inline test
