Chip-8 emulator with own assembler and disassembler. GUI for this emulator is implemented with raylib.
Assembler supports labels and simple variable constants. See chip8_res directory for examples.
At the moment of writing, raylib which is used in for GUI implementation is unavailable from (official) Ubuntu package repositories. See guides in raylib wiki to install it on your system. Raylib version 4.0.0 should work.
Run make to compile this project.
Compiling a chip-8 program and running the binaries:
./assembler chip8_res/button-test.asm button-test.ch8
./emulator button-test.ch8
Disassembling a chip-8 binary:
./assembler button-test.ch8 button-test.asm.2 -d
ESC will quit the emulator.
Input keys:
1-2-3-4
q-w-e-r
a-s-d-f
z-x-c-v
x, y = Number of register V used
nnn = 12-bit value
nn = 8-bit value
n = 4-bit value
| Opcode | Mnemonic | Description |
|---|---|---|
| 00E0 | CLS | Clear the display |
| 00EE | RET | Return from a subroutine |
| 1nnn | JMP nnn | Jump to a location nnn |
| 2nnn | CALL nnn | Call subroutine at nnn |
| 3xnn | SE Vx, nn | Skip next instruction if Vx == nn |
| 4xnn | SNE Vx, nn | Skip next instruction if Vx != nn |
| 5xy0 | SE Vx, Vy | Skip next instruction if Vx == Vy |
| 6xnn | MOV Vx, nn | Vx = nn |
| 7xnn | ADD Vx, nn | Vx += nn |
| 8xy0 | MOV Vx, Vy | Vx = Vy |
| 8xy1 | OR Vx, Vy | Vx |
| 8xy2 | AND Vx, Vy | Vx &= Vy |
| 8xy3 | XOR Vx, Vy | Vx ^= Vy |
| 8xy4 | ADD Vx, Vy | Vx += Vy, if overflow Vf = 1 |
| 8xy5 | SUB Vx, Vy | Vx -= Vy, if no borrow Vf = 1 |
| 8xy6 | SHR Vx, Vy | Vx >>= 1, if LSB is 1 set Vf = 1 |
| 8xy7 | SUBN Vx, Vy | Vx = Vy - Vx, if no borrow Vf = 1 |
| 8xyE | SHL Vx, Vy | Vx <<= 1, if MSB is 1 set Vf = 1 |
| 9xy0 | JNE Vx, Vy | Vx != Vy, skip next instr |
| Annn | MOV nnn | I = nnn |
| Bnnn | JMP Vx, nnn | Jump to Vx + nnn |
| Cxnn | RND Vx, nn | Vx = RND & nn |
| Dxyn | DRW Vx, Vy, n | Draw sprite with height n from RAM[I] to position Vx,Vy |
| Ex9E | KE Vx | Skip next instruction if key Vx pressed |
| ExA1 | KNE Vx | Skip next instruction if key Vx not pressed |
| Fx07 | MOV Vx, DT | Vx = delay timer |
| Fx0A | MOV Vx, K | Vx = Key press, blocking |
| Fx15 | MOV DT, Vx | DT = Vx |
| Fx18 | MOV ST, Vx | ST = Vx |
| Fx1E | ADD I, Vx | I += Vx |
| Fx29 | MOV F, Vx | I = location of sprite for digit Vx |
| Fx33 | MOV B, Vx | Store BCD representation of Vx to memory starting from RAM[I] |
| Fx55 | MOV [I], Vx | RAM[I...] = V0 ... Vx |
| Fx65 | MOV Vx, [I] | Vx = RAM[I] |
| .... | NOP nnnn | No operation. Can be used to store data |
Audio not tested througly. It probably has some issues with the delay timer.
Assembler doesn't count comment lines and error messages can point to wrong rows which can cause headache.