The executor is coming along.

Graphics and sound related instructions are gonna remain unimplemented for a while as I focus on getting the generic CPU up, then a ROM buffer and eventually working out how to graphics.

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "celc8"
-version = "0.1.0"
+version = "0.1.1"
 edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

src/main.rs

@@ -28,6 +28,9 @@ impl Cpu {
 	fn indwrite(&mut self, value: u16) {
 		self.i = value;
 	}
+	fn incrementpc(&mut self) {
+		self.pc = self.pc + 2
+	}
 }
 
 struct Instruction {
@@ -198,11 +201,44 @@ fn decodetest(opcode: u16, expected: &str) {
 	}
 }
 
+fn execute(opcode: u16, instruction: Instruction, mut cpu: Cpu) -> Cpu {
+	let mut args: Vec<u16> = vec![];
+	let mut i = 0;
+
+	if instruction.masks.len() != 0 {
+		for mask in instruction.masks {
+			let shift = instruction.shifts[i];
+			args.push((opcode & mask) >> shift);
+			i = i + 1;
+		}
+	}
+
+	if instruction.name == "LD_VX_BYTE" {
+		cpu.regwrite(args[0] as usize, args[1] as u8);
+		cpu.incrementpc();
+	}
+	else { println!("Unimplemented instruction {}. Skipping.", instruction.name) }
+
+	return cpu;
+
+}
+
 fn main() {
-	let mut cpu = Cpu { memory: vec![0; 4096], pc: 0x200, registers: vec![0;16], i: 0, stack: vec![0; 16], sp: -1, dt: 0, st: 0 };
+	let mut cpu = Cpu { memory: vec![0; 4096], pc: 0x200, registers: vec![0; 16], i: 0, stack: vec![0; 16], sp: -1, dt: 0, st: 0 };
 	println!("CPU initialised!");
 	torture();
 	println!("If you see messages above that are about opcodes, there's a bug!");
+
+	println!("Executing LD_VX_BYTE with opcode 0x6010, register 0 should be 16.");
+	let mut opcode = 0x6010;
+	let mut instruction = disassemble(opcode);
+	cpu = execute(opcode, instruction, cpu);
+
+	println!("Register 0 is {}!", cpu.registers[0]);
+	println!("Executing CLS which is not implemented. There should be an unimplemented error.");
+	opcode = 0x00e0;
+	instruction = disassemble(opcode);
+	cpu = execute(opcode, instruction, cpu);
 }
 
 fn torture() {