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Fix build errors.

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This commit is contained in:
madmaurice 2023-08-26 21:17:47 +02:00
parent 8019408684
commit 8d063c08ca
4 changed files with 106 additions and 59 deletions
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5
Makeconf
View file

@ -1,5 +1,6 @@
modules := test \ modules := test \
memory/bus \ memory/bus \
memory/ram memory/ram \
cpu/decoder
CXX_FLAGS := -I $(CURDIR) CXX_FLAGS := -I $(CURDIR)

14
cpu/cpu.h
View file

@ -12,11 +12,6 @@ enum Flags {
F_CARRY = 0x1, F_CARRY = 0x1,
}; };
union Register_pair {
struct { u8 hi; u8 lo; }
u16 hilo;
};
struct Cpu_state { struct Cpu_state {
// Registers // Registers
union { union {
@ -50,11 +45,14 @@ private:
typedef u8 opcode_t; typedef u8 opcode_t;
private: private:
u8 readPC(); u8 readPC8();
u16 readPC16();
void pushStack(u8 data); void pushStack8(u8 data);
u8 popStack(); u8 popStack8();
void pushStack16(u16 data);
u16 popStack16();
public: public:
Cpu(); Cpu();

142
cpu/decoder.cpp
View file

@ -1,4 +1,5 @@
#include "cpu/cpu.h" #include "cpu/cpu.h"
#include "memory/mem_device.h"
u8 Cpu::readPC8() u8 Cpu::readPC8()
{ {
@ -14,26 +15,26 @@ u16 Cpu::readPC16()
return data; return data;
} }
void pushStack8(u8 data) void Cpu::pushStack8(u8 data)
{ {
bus->write8(state.SP, data); bus->write8(state.SP, data);
state.SP--; state.SP--;
} }
u8 popStack8() u8 Cpu::popStack8()
{ {
u8 data = bus->read8(state.SP); u8 data = bus->read8(state.SP);
state.SP++; state.SP++;
return data; return data;
} }
void pushStack16(u16 data) void Cpu::pushStack16(u16 data)
{ {
bus->write16(state.SP,data); bus->write16(state.SP,data);
state.SP-=2; state.SP-=2;
} }
void popStack16() u16 Cpu::popStack16()
{ {
u16 data = bus->read16(state.SP); u16 data = bus->read16(state.SP);
state.SP+=2; state.SP+=2;
@ -42,67 +43,114 @@ void popStack16()
void Cpu::step() void Cpu::step()
{ {
opcode_t op = readPC(); opcode_t op = readPC8();
int mcycles = 1; int mcycles = 1;
switch(op) { switch(op) {
0x00: // NOP case 0x00: break; // NOP
(void) ;;
0x01: // LD BC, n16 case 0x01: // LD BC, n16
state.BC = readPC16(); mcycles = 12;; state.BC = readPC16(); mcycles = 12; break;
0x11: // LD DE, n16 case 0x11: // LD DE, n16
state.DE = readPC16(); mcycles = 12;; state.DE = readPC16(); mcycles = 12; break;
0x21: // LD HL, n16 case 0x21: // LD HL, n16
state.HL = readPC16(); mcycles = 12;; state.HL = readPC16(); mcycles = 12; break;
0x31: // LD SP, n16 case 0x31: // LD SP, n16
state.SP = readPC16(); mcycles = 12;; state.SP = readPC16(); mcycles = 12; break;
0x02: // LD [BC], A case 0x02: // LD [BC], A
bus->write8(state.BC, state.A); mcycles = 8;; bus->write8(state.BC, state.A); mcycles = 8; break;
0x12: // LD [DE], A case 0x12: // LD [DE], A
bus->write8(state.DE, state.A); mcycles = 8;; bus->write8(state.DE, state.A); mcycles = 8; break;
0x22: // LD [HL+], A case 0x22: // LD [HL+], A
bus->write8(state.HL, state.A); state.HL++; mcycles = 8;; bus->write8(state.HL, state.A); state.HL++; mcycles = 8; break;
0x32: // LD [HL-], A case 0x32: // LD [HL-], A
bus->write8(state.HL, state.A); state.HL--; mcycles = 8;; bus->write8(state.HL, state.A); state.HL--; mcycles = 8; break;
0x03: // INC BC case 0x03: // INC BC
state.BC++; mcycles = 2;; state.BC++; mcycles = 2; break;
0x13: // INC DE case 0x13: // INC DE
state.DE++; mcycles = 2;; state.DE++; mcycles = 2; break;
0x23: // INC HL case 0x23: // INC HL
state.HL++; mcycles = 2;; state.HL++; mcycles = 2; break;
0x33: // INC SP case 0x33: // INC SP
state.SP++; mcycles = 2;; state.SP++; mcycles = 2; break;
0x04: // INC B case 0x04: // INC B
state.B++; state.B++;
state.zero = (state.B == 0); state.zero = (state.B == 0);
state.subtract = false; state.subtract = false;
state.halfcarry = (state.B & 0x0F == 0); state.halfcarry = (state.B & 0x0F == 0);
; break;
0x14: // INC D case 0x14: // INC D
state.D++; state.D++;
state.zero = (state.D == 0); state.zero = (state.D == 0);
state.subtract = false; state.subtract = false;
state.halfcarry = (state.D & 0x0F == 0); state.halfcarry = (state.D & 0x0F == 0);
; break;
0x24: // INC H case 0x24: // INC H
state.H++; state.H++;
state.zero = (state.H == 0); state.zero = (state.H == 0);
state.subtract = false; state.subtract = false;
state.halfcarry = (state.H & 0x0F == 0); state.halfcarry = (state.H & 0x0F == 0);
; break;
0x34: // INC [HL] case 0x34: // INC [HL]
u8 data = bus->read8(state.HL); {
data++; u8 data = bus->read8(state.HL);
bus->write8(state.HL, data); data++;
state.zero = (data == 0); bus->write8(state.HL, data);
state.subtract = false; state.zero = (data == 0);
state.halfcarry = (data & 0x0F == 0); state.subtract = false;
state.halfcarry = (data & 0x0F == 0);
mcycles = 3;
}
break;
case 0x05: // INC B
state.B--;
state.zero = (state.B == 0);
state.subtract = true;
state.halfcarry = (state.B & 0x0F == 0x0F);
break;
case 0x15: // INC D
state.D--;
state.zero = (state.D == 0);
state.subtract = true;
state.halfcarry = (state.D & 0x0F == 0x0F);
break;
case 0x25: // INC H
state.H--;
state.zero = (state.H == 0);
state.subtract = true;
state.halfcarry = (state.H & 0x0F == 0x0F);
break;
case 0x35: // INC [HL]
{
u8 data = bus->read8(state.HL);
data--;
bus->write8(state.HL, data);
state.zero = (data == 0);
state.subtract = true;
state.halfcarry = (data & 0x0F == 0x0F);
mcycles = 3;
}
break;
case 0x06: // LD B, n8
state.B = readPC8();
mcycles = 2;
break;
case 0x16: // LD D, n8
state.D = readPC8();
mcycles = 2;
break;
case 0x26: // LD H, n8
state.H = readPC8();
mcycles = 2;
break;
case 0x36: // LD [HL], n8
bus->write8(state.HL, readPC8());
mcycles = 3; mcycles = 3;
; break;
} }
} }

4
memory/ram.cpp
View file

@ -4,7 +4,7 @@ RAM::RAM(u16 size) : size(size), readonly(false) {
memory = new u8[size]; memory = new u8[size];
} }
RAM::RAM(u8* memory, u16 size, bool readonly = false) RAM::RAM(u8* memory, u16 size, bool readonly)
: memory(memory), size(size), readonly(readonly) : memory(memory), size(size), readonly(readonly)
{} {}
@ -25,7 +25,7 @@ void RAM::write16(u16 addr, u16 data) {
} }
u16 RAM::read16(u16 addr) { u16 RAM::read16(u16 addr) {
if(addr >= size - 1) return; if(addr >= size - 1) return 0xFFFFu;
u16 *ptr = (u16*)&memory[addr]; u16 *ptr = (u16*)&memory[addr];
return *ptr; return *ptr;
} }