71 lines
1.8 KiB
Markdown
71 lines
1.8 KiB
Markdown
# 8-Bit CPU Emulator
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## CPU Architecture
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- Word Size
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- **Data Width:** 8 bits
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- **Address width:** 16 bits
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- **Address space:** 64 KB (0x0000-0xFFFF)
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## Supported Instructions
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| Instruction | Syntax |
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| ----------- | ---------------- |
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| MOV | mov dest, src OR mov reg, imm |
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| ADD | add r1, r2 OR add reg, imm |
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| SUB | sub r1, r2 OR sub reg, imm |
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| JMP | jmp addr OR jmp addr |
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| JZ | jz addr OR jz addr |
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| JNZ | jnz addr OR jnz addr |
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| CMP | cmp r1, r2 OR cmp reg, imp |
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| MUL | mul r1, r2 |
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| DIV | div r1, r2 |
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| CALL | call \<label\> |
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| SYS | sys \<syscall_no\> |
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| HLT (Halt) | hlt |
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## Registers
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| Register | Size | Description |
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| -------- | ------ | ------------------------------ |
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| A | 8-bit | General |
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| B | 8-bit | General |
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| C | 8-bit | General |
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| D | 8-bit | General |
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| PC | 16-bit | Program Counter |
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| SP | 16-bit | Stack pointer |
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## Flags
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| Flag | Description |
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| ----- | ------------ |
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| Z | Zero Flag |
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| C | Carry/Borrow |
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## Syscalls
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| Imm | Meaning |
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| --- | ------- |
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| 0 | Exit Program |
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| 1 | Print register A as integer |
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| 2 | Print register A as ASCII char |
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# Usage
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```bash
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cargo run -- --f <examples/filename.asc>
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```
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## Todo
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- [x] Assembler
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- [x] Lexer/Tokenizer
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- [x] Add label support (supporting JMP/JZ/JNZ)
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- [x] Add instructions
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- [x] CMP
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- [x] MUL
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- [x] DIV
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- [x] CALL
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- [x] RET
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- [x] SYS
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- [ ] Better Error handling
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- [ ] TUI Debugger
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