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Emulator: Implement 16-bit INC opcode

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Riyyi
2022-08-28 18:12:19 +02:00
parent a7169addd8
commit 5015b9e59d
2 changed files with 47 additions and 18 deletions
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src/cpu.cpp
+42 -18
View File
@@ -70,6 +70,7 @@ void CPU::update()
case 0x00: nop(); break;
case 0x01: ldi16(); break;
case 0x02: ldr8(); break;
case 0x03: inc16(); break;
case 0x04: inc8(); break;
case 0x05: dec8(); break;
case 0x06: ldi8(); break;
@@ -84,6 +85,7 @@ void CPU::update()
case 0x0f: ra(); break;
case 0x11: ldi16(); break;
case 0x12: ldr8(); break;
case 0x13: inc16(); break;
case 0x14: inc8(); break;
case 0x15: dec8(); break;
case 0x16: ldi8(); break;
@@ -99,6 +101,7 @@ void CPU::update()
case 0x20: jrs8(); break;
case 0x21: ldi16(); break;
case 0x22: ldr8(); break;
case 0x23: inc16(); break;
case 0x24: inc8(); break;
case 0x25: dec8(); break;
case 0x26: ldi8(); break;
@@ -113,6 +116,7 @@ void CPU::update()
case 0x30: jrs8(); break;
case 0x31: ldi16(); break;
case 0x32: ldr8(); break;
case 0x33: inc16(); break;
case 0x34: inc8(); break;
case 0x35: dec8(); break;
case 0x36: ldi8(); break;
@@ -525,24 +529,9 @@ void CPU::dec16()
{
uint8_t opcode = pcRead();
switch (opcode) {
case 0x0b: { // DEC BC
uint32_t data = (bc() - 1) & 0xffff;
m_c = data & 0xff;
m_b = data >> 8;
break;
}
case 0x1b: { // DEC DE
uint32_t data = (de() - 1) & 0xffff;
m_e = data & 0xff;
m_d = data >> 8;
break;
}
case 0x2b: { // DEC HL
uint32_t data = (hl() - 1) & 0xffff;
m_l = data & 0xff;
m_h = data >> 8;
break;
}
case 0x0b: /* DEC BC */ setBC(bc() - 1); break;
case 0x1b: /* DEC DE */ setDE(de() - 1); break;
case 0x2b: /* DEC HL */ setHL(hl() - 1); break;
case 0x3b: /* DEC SP */ m_sp = (m_sp - 1) & 0xffff; break;
default:
VERIFY_NOT_REACHED();
@@ -551,6 +540,21 @@ void CPU::dec16()
m_wait_cycles += 8;
}
void CPU::inc16()
{
uint8_t opcode = pcRead();
switch (opcode) {
case 0x03: /* INC BC */ setBC(bc() + 1); break;
case 0x13: /* INC DE */ setDE(de() + 1); break;
case 0x23: /* INC HL */ setHL(de() + 1); break;
case 0x24: /* INC SP */ m_sp = (m_sp + 1) & 0xffff; break;
default:
VERIFY_NOT_REACHED();
}
m_wait_cycles += 8;
}
// -------------------------------------
void CPU::ldi8()
@@ -1122,6 +1126,26 @@ void CPU::nop()
// -----------------------------------------
void CPU::setBC(uint32_t value)
{
m_c = value & 0xff;
m_b = (value & 0xff00) >> 8;
}
void CPU::setDE(uint32_t value)
{
m_e = value & 0xff;
m_d = (value & 0xff00) >> 8;
}
void CPU::setHL(uint32_t value)
{
m_l = value & 0xff;
m_h = (value & 0xff00) >> 8;
}
// -----------------------------------------
uint32_t CPU::pcRead()
{
uint32_t data = Emu::the().readMemory(m_pc) & 0xff;
src/cpu.h
+5
View File
@@ -38,6 +38,7 @@ public:
void addr16();
void adds8();
void dec16();
void inc16();
// -------------------------------------
// Bit Operations Instructions
@@ -102,6 +103,10 @@ public:
uint32_t pc() const { return m_pc; }
uint32_t sp() const { return m_sp; }
void setBC(uint32_t value);
void setDE(uint32_t value);
void setHL(uint32_t value);
private:
uint32_t pcRead();
uint32_t pcRead16() { return pcRead() | (pcRead() << 8); }