first tests

src/devices/mod.rs

@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright (c) 2024 Patrick_Pluto
+
+// This is an example implementation of a CPU emulator. You can copy this for your own custom ISA, or do something else.
+pub struct ExampleCPU {
+    debug: bool,
+    execution_pointer: u8,
+    operands: [u8; 3],
+    ram: [u8; 256],
+    registers: [u8; 8],
+}
+
+impl ExampleCPU {
+    // Here is where you can create your own CPU Instance.
+    pub fn create_instance(debug: bool, initial_state: [u8; 256]) -> ExampleCPU {
+        return ExampleCPU {
+            debug: debug,
+            execution_pointer: 0,
+            operands: [0; 3],
+            ram: initial_state,
+            registers: [0; 8],
+        };
+    }
+
+    // This fetches the operands, based on the position of the execution_pointer, then runs the selected instruction.
+    pub fn fetch_and_decode(&mut self) {
+        self.operands[0] = self.ram[self.execution_pointer as usize];
+        self.operands[1] = self.ram[(self.execution_pointer + 1) as usize];
+        self.operands[2] = self.ram[(self.execution_pointer + 2) as usize];
+        println!(
+            "0x{:02X} 0x{:02X} 0x{:02X}",
+            self.operands[0], self.operands[1], self.operands[2]
+        );
+        match self.operands[0] {
+            0x00 => self.nop(),
+            0x01 => self.load(),
+            0x02 => self.store(),
+            0x03 => self.add(),
+            0x04 => self.sub(),
+            0x05 => self.jump(),
+            0x06 => self.jpiz(),
+            _ => self.nop(),
+        };
+    }
+
+    // Here is where all of the implementations of the instructions should go.
+    fn nop(&mut self) {
+        self.execution_pointer += 1;
+    }
+
+    fn load(&mut self) {
+        self.registers[self.operands[1] as usize] = self.ram[self.operands[2] as usize];
+        self.execution_pointer += 3;
+    }
+
+    fn store(&mut self) {
+        self.ram[self.operands[1] as usize] = self.registers[self.operands[2] as usize];
+        self.execution_pointer += 3;
+    }
+
+    fn add(&mut self) {
+        self.registers[self.operands[1] as usize] += self.registers[self.operands[2] as usize];
+        self.execution_pointer += 3;
+    }
+
+    fn sub(&mut self) {
+        self.registers[self.operands[1] as usize] -= self.registers[self.operands[2] as usize];
+        self.execution_pointer += 3;
+    }
+
+    fn jump(&mut self) {
+        self.execution_pointer = self.operands[1];
+    }
+
+    fn jpiz(&mut self) {
+        if self.operands[2] == 0 {
+            self.execution_pointer = self.operands[1];
+        } else {
+            self.execution_pointer += 3;
+        }
+    }
+}

src/main.rs

@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright (c) 2024 Patrick_Pluto
+
+mod devices;
+
+fn main() {
+    let mut instance: devices::ExampleCPU = devices::ExampleCPU::create_instance(true, [0; 256]);
+    // change the instructions here
+    loop {
+        instance.fetch_and_decode();
+    }
+}