Simple Assembler for the Chip 8 Instruction set.
It supports varriable assignment for binary literals, hex literals using $ prefixes and labels (syntax label:) for use in jump or call instructions.
I tried sticking to this reference, but renamed some instructions (as I was annoyed by LD being used so often).
The architecture and code here is very much inspired by Robert Nystrom's excellent book Crafting Interpreters (you may notice some common function names :)).
I tried using "C++-light", i.e. only using some C++ features when it was convenient but trying to stick to C.
I've included tests for all instructions, you can run a test script that tests all instructions using make test.
To compile, create a folder named build and run make all -j to compile the executable ch8asm.x.
For a detailed explanation what each instruction does see here.
| Opcode | Instruction |
|---|---|
| 00E0 | CLS |
| 00EE | RET |
| 1nnn | JP addr |
| 2nnn | CALL addr |
| 3xkk | SE Vx, byte |
| 4xkk | SNE Vx, byte |
| 5xy0 | SE Vx, Vy |
| 6xkk | LD Vx, byte |
| 7xkk | ADD Vx, byte |
| 8xy0 | LD Vx, Vy |
| 8xy1 | OR Vx, Vy |
| 8xy2 | AND Vx, Vy |
| 8xy3 | XOR Vx, Vy |
| 8xy4 | ADD Vx, Vy |
| 8xy5 | SUB Vx, Vy |
| 8xy6 | SHR Vx{, Vy} |
| 8xy7 | SUBN Vx, Vy |
| 8xyE | SHL Vx{, Vy} |
| 9xy0 | SNE Vx, Vy |
| Annn | LD I, addr |
| Bnnn | JPO addr |
| Cxkk | RND Vx, byte |
| Dxyn | DRW Vx, Vy, nibble |
| Ex9E | SKP Vx |
| ExA1 | SKNP Vx |
| Fx07 | GDT Vx |
| Fx0A | WKP Vx |
| Fx15 | SDT Vx |
| Fx18 | SST Vx |
| Fx1E | ADD I, Vx |
| Fx29 | FNT Vx |
| Fx33 | BCD Vx |
| Fx55 | STV Vx |
| Fx65 | LDV Vx |