stp

snes-core/src/cpu/cpu.rs

@@ -3,7 +3,7 @@ use super::registers::Registers;
 pub struct CPU {
     pub registers: Registers,
     pub cycles: usize, // TODO: remove cycles from here
-    pub is_stopped: bool,
+    pub is_stopped: bool, // TODO: remove from here
     pub is_waiting_interrupt: bool,
 }
 

snes-core/src/cpu/instructionstemp/mod.rs

@@ -72,6 +72,7 @@ pub mod sep;
 pub mod sta;
 pub mod stx;
 pub mod sty;
+pub mod stp;
 pub mod bit_common;
 pub mod dec_common;
 pub mod decoder_common;

snes-core/src/cpu/instructionstemp/stp.rs

@@ -0,0 +1,42 @@
+use crate::cpu::{bus::Bus, registers::Registers};
+
+use crate::cpu::cycles;
+use super::{CPUInstruction, Decode};
+use super::decoder_common;
+
+static INSTR_NAME: &'static str = "STP";
+
+pub struct STP {}
+
+impl CPUInstruction for STP {
+    fn execute(&self, registers: &mut Registers, _bus: &mut Bus) {
+        registers.is_cpu_stopped = true;
+        let (bytes, cycles) = cycles::increment_cycles_stp();
+        registers.increment_pc(bytes); registers.cycles += cycles;
+    }
+}
+
+impl Decode for STP {
+    fn mnemonic(&self, _registers: &Registers, _bus: &Bus, opcode: u8) -> String {
+        decoder_common::mnemonic_single_byte_instr(opcode, INSTR_NAME)
+    }
+}
+
+
+#[cfg(test)]
+mod cpu_instructions_tests {
+    use super::*;
+
+    #[test]
+    fn test() {
+        let mut registers = Registers::new();
+        let mut bus = Bus::new();
+        registers.is_cpu_stopped = false;
+        registers.pc = 0x0000;
+        let instruction = STP{};
+        instruction.execute(&mut registers, &mut bus);
+        assert_eq!(registers.pc, 0x0001);
+        assert_eq!(registers.is_cpu_stopped, true);
+        assert_eq!(registers.cycles, 3);
+    }
+}

snes-core/src/cpu/registers.rs

@@ -11,6 +11,7 @@ pub struct Registers {
     pub dbr: u8, // Data bank register
     pub pc: u16, // Program counter
     pub emulation_mode: bool,
+    pub is_cpu_stopped: bool,
     pub cycles: usize,
 }
 
@@ -27,6 +28,7 @@ impl Registers {
             dbr: 0,
             pc: 0,
             emulation_mode: true,
+            is_cpu_stopped: false,
             cycles: 0,
         }
     }