Fix program counter issues
This commit is contained in:
paoda
parent
cb030b992d
commit
b320398394
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@ -1 +1,2 @@
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/target
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/games
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53
src/main.rs
53
src/main.rs
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@ -76,6 +76,8 @@ impl Chip8 {
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let nib_3 = (self.opcode & 0x00F0) >> 4; // 0xF
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let nib_4 = self.opcode & 0x000F; // 0x0
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self.pc += 2;
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// nib_ns are u16s so we waste 4 bytes here.
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match (nib_1, nib_2, nib_3, nib_4) {
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@ -155,13 +157,11 @@ impl Chip8 {
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fn cls(&mut self) {
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// Clear the display
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self.display.clear();
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self.pc += 1;
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}
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fn jmp_addr(&mut self, n_1: u16, n_2: u16, n_3: u16) {
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// sets the program counter to addr (nnn)
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self.pc = Self::convert_to_addr(n_1, n_2, n_3);
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self.pc += 1;
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}
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fn ret(&mut self) {
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@ -169,7 +169,6 @@ impl Chip8 {
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// then subtracts one (1) from the stack pointer
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self.pc = self.stack[self.sp as usize];
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self.sp -= 1;
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self.pc += 1;
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}
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fn call_addr(&mut self, n_1: u16, n_2: u16, n_3: u16) {
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@ -178,15 +177,12 @@ impl Chip8 {
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self.sp += 1;
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self.stack[self.sp as usize] = self.pc;
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self.pc = Self::convert_to_addr(n_1, n_2, n_3);
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self.pc += 1;
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}
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fn se_vx_byte(&mut self, x: u16, k_1: u16, k_2: u16) {
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// compares Vx to kk. If they are equal, pc is incremented by 2
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if self.v[x as usize] == Self::convert_to_byte(k_1, k_2) {
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self.pc += 2;
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} else {
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self.pc += 1;
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}
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}
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@ -194,8 +190,6 @@ impl Chip8 {
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// compares Vx to kk. If they are **not** equal, pc is incremented by 2
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if self.v[x as usize] != Self::convert_to_byte(k_1, k_2) {
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self.pc += 2;
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} else {
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self.pc += 1;
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}
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}
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@ -203,49 +197,41 @@ impl Chip8 {
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// compares Vx to Vy. If they are equal, pc is incremented by 2
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if self.v[x as usize] == self.v[y as usize] {
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self.pc += 2;
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} else {
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self.pc += 1;
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}
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}
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fn ld_vx_byte(&mut self, x: u16, k_1: u16, k_2: u16) {
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// put value kk into Vx
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self.v[x as usize] = Self::convert_to_byte(k_1, k_2);
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self.pc += 1;
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}
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fn add_vx_byte(&mut self, x: u16, k_1: u16, k_2: u16) {
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// calculate Vx + kk, then store it in Vx
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let x = x as usize;
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self.v[x] = self.v[x] + Self::convert_to_byte(k_1, k_2);
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self.pc += 1;
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}
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fn ld_vx_vy(&mut self, x: u16, y: u16) {
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// store Vy in Vx
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self.v[x as usize] = self.v[y as usize];
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self.pc += 1;
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}
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fn or_vx_vy(&mut self, x: u16, y: u16) {
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// calc bitwise OR on Vx and Vy, then store in Vx
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let x = x as usize;
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self.v[x] = self.v[x] | self.v[y as usize];
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self.pc += 1;
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}
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fn and_vx_vy(&mut self, x: u16, y: u16) {
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// calc bitwise AND on Vx and Vy, then store in Vx
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let x = x as usize;
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self.v[x] = self.v[x] & self.v[y as usize];
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self.pc += 1;
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}
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fn xor_vx_vy(&mut self, x: u16, y: u16) {
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// calc bitwise XOR on Vx and Vy, then store in Vx
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let x = x as usize;
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self.v[x] = self.v[x] ^ self.v[y as usize];
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self.pc += 1;
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}
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fn add_vx_vy(&mut self, x: u16, y: u16) {
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@ -257,7 +243,6 @@ impl Chip8 {
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let (res, did_overflow) = self.v[x].overflowing_add(self.v[y as usize]);
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self.v[0xF as usize] = if did_overflow { 1 } else { 0 };
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self.v[x] = res;
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self.pc += 1;
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}
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fn sub_vx_vy(&mut self, x: u16, y: u16) {
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@ -268,7 +253,6 @@ impl Chip8 {
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self.v[0xF as usize] = if vx > vy { 1 } else { 0 };
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self.v[x as usize] = vx - vy;
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self.pc += 1;
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}
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fn shr_vx(&mut self, x: u16) {
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@ -278,7 +262,6 @@ impl Chip8 {
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self.v[0xF as usize] = if (self.v[x] & 1) == 1 { 1 } else { 0 };
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self.v[x] = self.v[x] >> 1;
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self.pc += 1;
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}
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fn subn_vx_vy(&mut self, x: u16, y: u16) {
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@ -289,7 +272,6 @@ impl Chip8 {
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self.v[0xF as usize] = if vy > vx { 1 } else { 0 };
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self.v[x as usize] = vy - vx;
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self.pc += 1;
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}
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fn shl_vx(&mut self, x: u16) {
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@ -299,28 +281,23 @@ impl Chip8 {
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self.v[0xF as usize] = if (self.v[x] & 0x80) == 1 { 1 } else { 0 };
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self.v[x] = self.v[x] << 1;
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self.pc += 1;
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}
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fn sne_vx_vy(&mut self, x: u16, y: u16) {
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// if Vx != vy program counter is increased by 2
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if self.v[x as usize] != self.v[y as usize] {
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self.pc += 2;
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} else {
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self.pc += 1;
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}
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}
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fn ld_i_addr(&mut self, n_1: u16, n_2: u16, n_3: u16) {
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// set i to addr
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self.i = Self::convert_to_addr(n_1, n_2, n_3);
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self.pc += 1;
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}
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fn jmp_v0_addr(&mut self, n_1: u16, n_2: u16, n_3: u16) {
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// set program counter to addr + V0
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self.pc = Self::convert_to_addr(n_1, n_2, n_3) + self.v[0 as usize] as u16;
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self.pc += 1;
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}
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fn rnd_vx_byte(&mut self, x: u16, k_1: u16, k_2: u16) {
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@ -328,7 +305,6 @@ impl Chip8 {
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// AND with the value of kk, then store in Vx
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self.v[x as usize] = rand::random::<u8>() & Self::convert_to_byte(k_1, k_2);
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self.pc += 1;
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}
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fn drw_vx_vy_nib(&mut self, x: u16, y: u16, nib: u16) {
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@ -351,11 +327,7 @@ impl Chip8 {
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if let Some(key) = self.key {
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if self.v[x as usize] == key {
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self.pc += 2;
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} else {
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self.pc += 1;
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}
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} else {
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self.pc += 1;
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}
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}
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@ -366,8 +338,6 @@ impl Chip8 {
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Some(key) => {
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if key != self.v[x as usize] {
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self.pc += 2;
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} else {
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self.pc += 1;
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}
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}
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None => self.pc += 2,
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@ -377,37 +347,31 @@ impl Chip8 {
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fn ld_vx_dt(&mut self, x: u16) {
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// set Vx to be the value of the delay timer
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self.v[x as usize] = self.delay.get();
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self.pc += 1;
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}
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fn ld_vx_k(&mut self, x: u16) {
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// wait (blocking) until a key is pressed
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// once pressed, store in Vx
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loop {
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if let Some(key) = self.key {
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self.v[x as usize] = key;
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break;
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}
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match self.key {
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Some(key) => self.v[x as usize] = key,
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None => self.pc -= 2,
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}
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self.pc += 1;
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}
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fn ld_dt_vx(&mut self, x: u16) {
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// set delay timer to be value of Vx
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self.delay.set(self.v[x as usize]);
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self.pc += 1;
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}
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fn ld_st_vx(&mut self, x: u16) {
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// set sound timer to be value of Vx
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self.delay.set(self.v[x as usize]);
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self.pc += 1;
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}
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fn add_i_vx(&mut self, x: u16) {
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// set I to be I + Vx
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self.i = self.i + self.v[x as usize] as u16;
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self.pc += 1;
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}
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fn ld_f_vx(&mut self, _x: u16) {
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@ -428,7 +392,6 @@ impl Chip8 {
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self.memory[i] = hundreds;
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self.memory[i + 1] = tens;
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self.memory[i + 2] = ones;
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self.pc += 1;
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}
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fn ld_i_vx(&mut self, x: u16) {
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@ -437,7 +400,6 @@ impl Chip8 {
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for n in 0..=(x as usize) {
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self.memory[self.i as usize + n] = self.v[n];
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}
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self.pc += 1;
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}
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fn ld_vx_i(&mut self, x: u16) {
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@ -447,7 +409,6 @@ impl Chip8 {
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for n in 0..=x {
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self.v[n] = self.memory[self.i as usize + n];
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}
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self.pc += 1;
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}
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fn convert_to_byte(k_1: u16, k_2: u16) -> u8 {
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@ -572,7 +533,7 @@ fn main() {
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let mut chip8: Chip8 = Default::default();
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chip8
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.load_rom(Path::new("C:\\Users\\paoda\\Documents\\chip8_roms\\TICTAC"))
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.load_rom(Path::new("./games/c8games/TICTAC"))
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.expect("Unable to load ROM");
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loop {
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