diff options
Diffstat (limited to 'src/cpu')
| -rw-r--r-- | src/cpu/chip.rs | 67 |
1 files changed, 44 insertions, 23 deletions
diff --git a/src/cpu/chip.rs b/src/cpu/chip.rs index 7b62a24..847840c 100644 --- a/src/cpu/chip.rs +++ b/src/cpu/chip.rs @@ -227,8 +227,8 @@ impl Chip { (0b00, r8, 0b101) => { self.dec_r8(r8) }, //DEC r8 (0b00, r8, 0b110) => { self.ld_r8_n8(r8) }, //LD r8, u8 (0b00, opcode, 0b111) => { self.special_opcodes(opcode) }, //Opcode grp 1 - (0b01, 0b110, 0b110) => { }, //HALT - (0b01, src_r8, dst_r8) => { }, //LD r8, r8 + (0b01, 0b110, 0b110) => { self.halt() }, //HALT + (0b01, dst_r8, src_r8) => { self.ld_r8_r8(src_r8, dst_r8) }, //LD r8, r8 (0b10, op, r8) => { self.alu_a_r8(op, r8); }, //ALU A, r8 (0b11, 0b000..=0b011, 0b000) => { }, //RET condition (0b11, 0b100, 0b000) => { }, //LD (FF00 + u8), A @@ -255,7 +255,7 @@ impl Chip { // 0x00 => { println!("NOOP!") } // 0x32 => { self.ldd_hl_a() } // 0x0e | 0x06 => { self.ld_rr(); next = 1; } -// 0xa8..=0xaf => { self.xor_r() } +// 0xa8..=0xaf => { self.xor_a_r8() } // 0x01 | 0x11 | 0x21 | 0x31 => { self.ld_rr_nn(); next = 2; }, // _ => { println!("Error: 0x{:02X} not implemented!", self.instr); std::process::exit(1); } // } @@ -263,6 +263,17 @@ impl Chip { } + // Load value from dst_r8 into src_r8. When called as LD r1 r2, this method + // is called as ld_r8_r8(r2, r1) (Notice the inversion) + fn ld_r8_r8(&mut self, src_r8: u8, dst_r8: u8) { + let value = self.get_r8_register(src_r8); + self.set_r8_register(dst_r8, value); + + } + //TODO - Respond to interrupt + fn halt(&mut self) { + + } //TODO fn special_opcodes(&mut self, opcode: u8) { } @@ -368,34 +379,28 @@ impl Chip { self.write_memory(address + 1, (self.sp >> 8) as u8); } + //All math based operations are processed here fn alu_a_r8(&mut self, opcode: u8, r8: u8) { match opcode { - 1 => { self.adc_r(r8) }, - 5 => { self.xor_r(r8) }, + 0b000 => { self.add_a_r8(r8) }, + 0b001 => { self.adc_a_r8(r8) }, + 0b010 => { self.sub_a_r8(r8) }, + 0b011 => { self.sbc_a_r8(r8) }, + 0b100 => { self.and_a_r8(r8) }, + 0b101 => { self.xor_a_r8(r8) }, + 0b110 => { self.or_a_r8(r8) }, + 0b111 => { self.cp_a_r8(r8) }, _ => {} } } - - fn ld_rr(&mut self) { - match self.instr { - 0x0e => { self.c = self.byte2 }, - 0x06 => { self.b = self.byte2 }, - _ => {}, - } - } - - fn ldd_hl_a(&mut self) { - let mut pc = ((self.h as u16) << 8) as u16 | self.l as u16; - self.write_memory(pc, self.a); - pc -= 1; - self.h = (pc >> 8) as u8; - self.l = (pc << 8 >> 8) as u8; - } - fn adc_r(&mut self, r8: u8) { + fn add_a_r8(&mut self, r8: u8) { + } + fn adc_a_r8(&mut self, r8: u8) { self.a += self.flags.carry + r8; } - fn xor_r(&mut self, r8: u8) { + + fn xor_a_r8(&mut self, r8: u8) { let value = match r8 { 0 => { self.b }, 1 => { self.c }, @@ -413,6 +418,22 @@ impl Chip { self.a = self.a ^ value; self.flags.zero = (self.a == 0) as u8 } + + fn ld_rr(&mut self) { + match self.instr { + 0x0e => { self.c = self.byte2 }, + 0x06 => { self.b = self.byte2 }, + _ => {}, + } + } + + fn ldd_hl_a(&mut self) { + let mut pc = ((self.h as u16) << 8) as u16 | self.l as u16; + self.write_memory(pc, self.a); + pc -= 1; + self.h = (pc >> 8) as u8; + self.l = (pc << 8 >> 8) as u8; + } fn jmp_nn(&mut self) { println!("{:02X}, {:02X}", self.byte2, self.byte3); |