chore: docs

rkdud007 · Oct 28, 2024 · 46f788f · 46f788f
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diff --git a/README.md b/README.md
@@ -1,3 +1,48 @@
 # SolChip8
 
 [Chip8](https://en.wikipedia.org/wiki/CHIP-8) Emulator written in Solidity.
+
+Got helped alot from [An Introduction to Chip-8 Emulation using the Rust Programming Language](https://aquova.net/chip8/chip8.pdf).
+
+- boolean screen support (64 x 32 pixels)
+- 16 registers
+- 4096 bytes of RAM
+
+### **Supported CHIP-8 Opcodes**
+
+| Opcode | Mnemonic          | Description                                                         |
+| ------ | ----------------- | ------------------------------------------------------------------- |
+| 00E0   | **CLS**           | Clear the display                                                   |
+| 00EE   | **RET**           | Return from a subroutine                                            |
+| 1NNN   | **JP NNN**        | Jump to address `NNN`                                               |
+| 2NNN   | **CALL NNN**      | Call subroutine at `NNN`                                            |
+| 3XNN   | **SE Vx, NN**     | Skip next instruction if `Vx` equals `NN`                           |
+| 4XNN   | **SNE Vx, NN**    | Skip next instruction if `Vx` does not equal `NN`                   |
+| 5XY0   | **SE Vx, Vy**     | Skip next instruction if `Vx` equals `Vy`                           |
+| 6XNN   | **LD Vx, NN**     | Load value `NN` into register `Vx`                                  |
+| 7XNN   | **ADD Vx, NN**    | Add value `NN` to register `Vx`                                     |
+| 8XY0   | **LD Vx, Vy**     | Set `Vx` equal to `Vy`                                              |
+| 8XY1   | **OR Vx, Vy**     | Set `Vx` to `Vx` OR `Vy`                                            |
+| 8XY2   | **AND Vx, Vy**    | Set `Vx` to `Vx` AND `Vy`                                           |
+| 8XY3   | **XOR Vx, Vy**    | Set `Vx` to `Vx` XOR `Vy`                                           |
+| 8XY4   | **ADD Vx, Vy**    | Add `Vy` to `Vx`, set VF to carry                                   |
+| 8XY5   | **SUB Vx, Vy**    | Subtract `Vy` from `Vx`, set VF to NOT borrow                       |
+| 8XY6   | **SHR Vx**        | Shift `Vx` right by 1, set VF to least significant bit              |
+| 8XY7   | **SUBN Vx, Vy**   | Set `Vx` to `Vy` minus `Vx`, set VF to NOT borrow                   |
+| 8XYE   | **SHL Vx**        | Shift `Vx` left by 1, set VF to most significant bit                |
+| 9XY0   | **SNE Vx, Vy**    | Skip next instruction if `Vx` does not equal `Vy`                   |
+| ANNN   | **LD I, NNN**     | Set `I` to address `NNN`                                            |
+| BNNN   | **JP V0, NNN**    | Jump to address `V0 + NNN`                                          |
+| CXNN   | **RND Vx, NN**    | Set `Vx` to random byte AND `NN`                                    |
+| DXYN   | **DRW Vx, Vy, N** | Draw sprite at (`Vx`, `Vy`) with height `N`, set VF on collision    |
+| EX9E   | **SKP Vx**        | Skip next instruction if key `Vx` is pressed                        |
+| EXA1   | **SKNP Vx**       | Skip next instruction if key `Vx` is not pressed                    |
+| FX07   | **LD Vx, DT**     | Set `Vx` to the value of the delay timer                            |
+| FX0A   | **LD Vx, K**      | Wait for a key press, store the value in `Vx`                       |
+| FX15   | **LD DT, Vx**     | Set the delay timer to `Vx`                                         |
+| FX18   | **LD ST, Vx**     | Set the sound timer to `Vx`                                         |
+| FX1E   | **ADD I, Vx**     | Add `Vx` to `I`                                                     |
+| FX29   | **LD F, Vx**      | Set `I` to the location of the sprite for digit `Vx`                |
+| FX33   | **LD B, Vx**      | Store BCD representation of `Vx` in memory at `I`, `I+1`, and `I+2` |
+| FX55   | **LD [I], Vx**    | Store registers `V0` to `Vx` in memory starting at `I`              |
+| FX65   | **LD Vx, [I]**    | Read registers `V0` to `Vx` from memory starting at `I`             |
diff --git a/src/Emu.sol b/src/Emu.sol
@@ -504,10 +504,6 @@ contract Emu {
         return emu.pc;
     }
 
-    function getFontset() public view returns (uint8[80] memory) {
-        return FONTSET;
-    }
-
     function getRAMValueAt(uint256 index) public view returns (uint8) {
         require(index < RAM_SIZE, "RAM index out of bounds");
         return emu.ram[index];

diff --git a/test/Emu.t.sol b/test/Emu.t.sol
@@ -17,11 +17,7 @@ contract EmuTest is Test {
 
         // pc == START_ADDR
         uint16 pc = emulator.getPC();
-        assertEq(
-            pc,
-            0x200,
-            "Program counter should be reset to START_ADDR (0x200)"
-        );
+        assertEq(pc, 0x200, "Program counter should be reset to START_ADDR (0x200)");
     }
 
     function testExecuteSetVx() public {
@@ -106,13 +102,7 @@ contract EmuTest is Test {
         assertEq(xPos, 0, "Should be 0");
         assertEq(yPos, 0, "Should be 0");
 
-        uint8[5] memory pixelData = [
-            program[12],
-            program[13],
-            program[14],
-            program[15],
-            program[16]
-        ];
+        uint8[5] memory pixelData = [program[12], program[13], program[14], program[15], program[16]];
 
         // Iterate over each row of the pixel
         for (uint8 row = 0; row < 5; row++) {
@@ -133,11 +123,7 @@ contract EmuTest is Test {
                 console.log("Index: %s", index);
 
                 // Assert that the display pixel matches the expected value
-                assertEq(
-                    display[index],
-                    pixelShouldBeSet,
-                    "Pixel should be set"
-                );
+                assertEq(display[index], pixelShouldBeSet, "Pixel should be set");
             }
         }
     }