handle SE instruction

1 files changed, 13 insertions, 7 deletions

diff --git a/src/chip8.rs b/src/chip8.rs
index 99ce428..0ea6d6d 100644
--- a/src/chip8.rs
+++ b/src/chip8.rs
@@ -49,10 +49,10 @@ impl Chip8 {
     pub fn cycle(&mut self) {
         let pc = self.pc as usize;
         let opcode = ((self.memory[pc] as u16) << 8) | self.memory[pc + 1] as u16;
-        let x = (opcode & 0x0F00) >> 8;
-        let y = (opcode & 0x00F0) >> 4;
+        let x = ((opcode & 0x0F00) >> 8) as usize;
+        let y = ((opcode & 0x00F0) >> 4) as usize;
         let n = opcode & 0x000F;
-        let nn = opcode & 0x00FF;
+        let nn = (opcode & 0x00FF) as u8;
         let nnn = opcode & 0x0FFF;
         self.pc += 2;
         match opcode & 0xF000 {
@@ -71,13 +71,19 @@ impl Chip8 {
                 eprintln!("JP {}", nnn);
                 self.pc = nnn;
             }
+            0x3000 => {
+                eprintln!("SE V{}, {}", x, nn);
+                if self.v[x] == nn {
+                    self.pc += 2;
+                }
+            }
             0x6000 => {
                 eprintln!("LD V{}, {}", x, nn);
-                self.v[x as usize] = nn as u8;
+                self.v[x] = nn;
             }
             0x7000 => {
                 eprintln!("ADD V{}, {}", x, nn);
-                self.v[x as usize] += nn as u8;
+                self.v[x] += nn;
             }
             0xA000 => {
                 eprintln!("LD I, {}", nnn);
@@ -85,8 +91,8 @@ impl Chip8 {
             }
             0xD000 => {
                 eprintln!("DRW V{}, V{}, {}", x, y, n);
-                let vx = self.v[x as usize] as u16;
-                let vy = self.v[y as usize] as u16;
+                let vx = self.v[x] as u16;
+                let vy = self.v[y] as u16;
                 self.v[0xF] = 0;
                 for yy in 0..n {
                     let pixel = self.memory[(self.i + yy) as usize];