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Emulator: Implement RES opcodes

master
Riyyi 3 years ago
parent
6ada7261e7
commit
e35aa06471
2 changed files with 102 additions and 0 deletions
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  1. 101
      src/cpu-prefix.cpp
  2. 1
      src/cpu.h

101
src/cpu-prefix.cpp
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@ -23,6 +23,9 @@ void CPU::prefix()
if (opcode >= 0x40 && opcode <= 0x7f) { if (opcode >= 0x40 && opcode <= 0x7f) {
bit(); bit();
} }
else if (opcode >= 0x80 && opcode <= 0xbf) {
res();
}
else { else {
print("opcode {:#04x} not implemented\n", opcode); print("opcode {:#04x} not implemented\n", opcode);
print("immediate: {:#04x}\n", m_pc, pcRead()); print("immediate: {:#04x}\n", m_pc, pcRead());
@ -131,3 +134,101 @@ void CPU::bit()
VERIFY_NOT_REACHED(); VERIFY_NOT_REACHED();
} }
} }
void CPU::res()
{
auto reset_bit = [this](uint32_t bit, uint32_t& register_) -> void {
// RES b,r8
m_wait_cycles += 8;
// Reset bit at position 'x' in register r8
register_ = register_ & (~bit);
};
auto reset_bit_hl = [this](uint32_t bit) -> void {
// RES b,(HL)
m_wait_cycles += 16;
// Set bit at postition 'x' in the byte pointed by HL to 0
uint32_t data = read(hl());
data = data & (~bit);
write(hl(), data);
};
uint8_t opcode = pcRead();
switch (opcode) {
case 0x40: /* RES 0,B */ reset_bit(0x01, m_b); break;
case 0x41: /* RES 0,C */ reset_bit(0x01, m_c); break;
case 0x42: /* RES 0,D */ reset_bit(0x01, m_d); break;
case 0x43: /* RES 0,E */ reset_bit(0x01, m_e); break;
case 0x44: /* RES 0,H */ reset_bit(0x01, m_h); break;
case 0x45: /* RES 0,L */ reset_bit(0x01, m_l); break;
case 0x46: /* RES 0,(HL) */ reset_bit_hl(0x01); break;
case 0x47: /* RES 0,A */ reset_bit(0x01, m_a); break;
case 0x48: /* RES 1,B */ reset_bit(0x02, m_b); break;
case 0x49: /* RES 1,C */ reset_bit(0x02, m_c); break;
case 0x4a: /* RES 1,D */ reset_bit(0x02, m_d); break;
case 0x4b: /* RES 1,E */ reset_bit(0x02, m_e); break;
case 0x4c: /* RES 1,H */ reset_bit(0x02, m_h); break;
case 0x4d: /* RES 1,L */ reset_bit(0x02, m_l); break;
case 0x4e: /* RES 1,(HL) */ reset_bit_hl(0x02); break;
case 0x4f: /* RES 1,A */ reset_bit(0x02, m_a); break;
case 0x50: /* RES 2,B */ reset_bit(0x04, m_b); break;
case 0x51: /* RES 2,C */ reset_bit(0x04, m_c); break;
case 0x52: /* RES 2,D */ reset_bit(0x04, m_d); break;
case 0x53: /* RES 2,E */ reset_bit(0x04, m_e); break;
case 0x54: /* RES 2,H */ reset_bit(0x04, m_h); break;
case 0x55: /* RES 2,L */ reset_bit(0x04, m_l); break;
case 0x56: /* RES 2,(HL) */ reset_bit_hl(0x04); break;
case 0x57: /* RES 2,A */ reset_bit(0x04, m_a); break;
case 0x58: /* RES 3,B */ reset_bit(0x08, m_b); break;
case 0x59: /* RES 3,C */ reset_bit(0x08, m_c); break;
case 0x5a: /* RES 3,D */ reset_bit(0x08, m_d); break;
case 0x5b: /* RES 3,E */ reset_bit(0x08, m_e); break;
case 0x5c: /* RES 3,H */ reset_bit(0x08, m_h); break;
case 0x5d: /* RES 3,L */ reset_bit(0x08, m_l); break;
case 0x5e: /* RES 3,(HL) */ reset_bit_hl(0x08); break;
case 0x5f: /* RES 3,A */ reset_bit(0x08, m_a); break;
case 0x60: /* RES 4,B */ reset_bit(0x10, m_b); break;
case 0x61: /* RES 4,C */ reset_bit(0x10, m_c); break;
case 0x62: /* RES 4,D */ reset_bit(0x10, m_d); break;
case 0x63: /* RES 4,E */ reset_bit(0x10, m_e); break;
case 0x64: /* RES 4,H */ reset_bit(0x10, m_h); break;
case 0x65: /* RES 4,L */ reset_bit(0x10, m_l); break;
case 0x66: /* RES 4,(HL) */ reset_bit_hl(0x10); break;
case 0x67: /* RES 4,A */ reset_bit(0x10, m_a); break;
case 0x68: /* RES 5,B */ reset_bit(0x20, m_b); break;
case 0x69: /* RES 5,C */ reset_bit(0x20, m_c); break;
case 0x6a: /* RES 5,D */ reset_bit(0x20, m_d); break;
case 0x6b: /* RES 5,E */ reset_bit(0x20, m_e); break;
case 0x6c: /* RES 5,H */ reset_bit(0x20, m_h); break;
case 0x6d: /* RES 5,L */ reset_bit(0x20, m_l); break;
case 0x6e: /* RES 5,(HL) */ reset_bit_hl(0x20); break;
case 0x6f: /* RES 5,A */ reset_bit(0x20, m_a); break;
case 0x70: /* RES 6,B */ reset_bit(0x40, m_b); break;
case 0x71: /* RES 6,C */ reset_bit(0x40, m_c); break;
case 0x72: /* RES 6,D */ reset_bit(0x40, m_d); break;
case 0x73: /* RES 6,E */ reset_bit(0x40, m_e); break;
case 0x74: /* RES 6,H */ reset_bit(0x40, m_h); break;
case 0x75: /* RES 6,L */ reset_bit(0x40, m_l); break;
case 0x76: /* RES 6,(HL) */ reset_bit_hl(0x40); break;
case 0x77: /* RES 6,A */ reset_bit(0x40, m_a); break;
case 0x78: /* RES 7,B */ reset_bit(0x80, m_b); break;
case 0x79: /* RES 7,C */ reset_bit(0x80, m_c); break;
case 0x7a: /* RES 7,D */ reset_bit(0x80, m_d); break;
case 0x7b: /* RES 7,E */ reset_bit(0x80, m_e); break;
case 0x7c: /* RES 7,H */ reset_bit(0x80, m_h); break;
case 0x7d: /* RES 7,L */ reset_bit(0x80, m_l); break;
case 0x7e: /* RES 7,(HL) */ reset_bit_hl(0x80); break;
case 0x7f: /* RES 7,A */ reset_bit(0x80, m_a); break;
default:
VERIFY_NOT_REACHED();
}
}

1
src/cpu.h
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@ -42,6 +42,7 @@ public:
// Bit Operations Instructions // Bit Operations Instructions
void bit(); void bit();
void res();
// ------------------------------------- // -------------------------------------
// Bit Shift Instructions // Bit Shift Instructions

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