mirror of
https://github.com/MoleskiCoder/EightBit.git
synced 2024-09-01 15:29:11 +00:00
666 lines
15 KiB
C++
666 lines
15 KiB
C++
#pragma once
|
|
|
|
// Auxiliary carry logic from https://github.com/begoon/i8080-core
|
|
|
|
#include "IntelProcessor.h"
|
|
#include "InputOutput.h"
|
|
|
|
namespace EightBit {
|
|
class Intel8080 : public IntelProcessor {
|
|
public:
|
|
typedef std::function<void()> instruction_t;
|
|
|
|
enum StatusBits {
|
|
SF = Bit7,
|
|
ZF = Bit6,
|
|
AC = Bit4,
|
|
PF = Bit2,
|
|
CF = Bit0,
|
|
};
|
|
|
|
enum AddressingMode {
|
|
Unknown,
|
|
Implied, // zero bytes
|
|
Immediate, // single byte
|
|
Absolute // two bytes, little endian
|
|
};
|
|
|
|
struct Instruction {
|
|
instruction_t vector = nullptr;
|
|
AddressingMode mode = Unknown;
|
|
std::string disassembly;
|
|
int count = 0;
|
|
};
|
|
|
|
Intel8080(Memory& memory, InputOutput& ports);
|
|
|
|
Signal<Intel8080> ExecutingInstruction;
|
|
|
|
const std::array<Instruction, 0x100>& getInstructions() const { return instructions; }
|
|
|
|
virtual register16_t& AF() override { return af; }
|
|
virtual register16_t& BC() override { return bc; }
|
|
virtual register16_t& DE() override { return de; }
|
|
virtual register16_t& HL() override { return hl; }
|
|
|
|
bool isInterruptable() const {
|
|
return m_interrupt;
|
|
}
|
|
|
|
int interrupt(uint8_t value) {
|
|
if (isInterruptable()) {
|
|
di();
|
|
return execute(value);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
virtual void initialise();
|
|
int step();
|
|
|
|
private:
|
|
InputOutput& m_ports;
|
|
|
|
std::array<Instruction, 0x100> instructions;
|
|
|
|
register16_t af;
|
|
register16_t bc;
|
|
register16_t de;
|
|
register16_t hl;
|
|
|
|
bool m_interrupt;
|
|
|
|
int execute(uint8_t opcode);
|
|
|
|
int execute(const Instruction& instruction) {
|
|
cycles = 0;
|
|
instruction.vector();
|
|
return cycles + instruction.count;
|
|
}
|
|
|
|
void adjustReservedFlags() {
|
|
F() = (F() | Bit1) & ~(Bit5 | Bit3);
|
|
}
|
|
|
|
static void adjustAuxiliaryCarryAdd(uint8_t& f, uint8_t before, uint8_t value, int calculation) {
|
|
setFlag(f, AC, calculateHalfCarryAdd(before, value, calculation));
|
|
}
|
|
|
|
static void adjustAuxiliaryCarrySub(uint8_t& f, uint8_t before, uint8_t value, int calculation) {
|
|
clearFlag(f, AC, calculateHalfCarrySub(before, value, calculation));
|
|
}
|
|
|
|
static void postIncrement(uint8_t& f, uint8_t value) {
|
|
adjustSZP<Intel8080>(f, value);
|
|
clearFlag(f, AC, lowNibble(value));
|
|
}
|
|
|
|
static void postDecrement(uint8_t& f, uint8_t value) {
|
|
adjustSZP<Intel8080>(f, value);
|
|
setFlag(f, AC, lowNibble(value) != Mask4);
|
|
}
|
|
|
|
static Instruction INS(instruction_t method, AddressingMode mode, std::string disassembly, int cycles);
|
|
Instruction UNKNOWN();
|
|
|
|
void installInstructions();
|
|
|
|
//
|
|
|
|
void compare(uint8_t value) {
|
|
auto check = A();
|
|
sub(check, value);
|
|
}
|
|
|
|
void anda(uint8_t value) {
|
|
auto& a = A();
|
|
auto& f = F();
|
|
setFlag(f, AC, (a | value) & Bit3);
|
|
clearFlag(f, CF);
|
|
adjustSZP<Intel8080>(f, a &= value);
|
|
}
|
|
|
|
void ora(uint8_t value) {
|
|
auto& f = F();
|
|
clearFlag(f, AC | CF);
|
|
adjustSZP<Intel8080>(f, A() |= value);
|
|
}
|
|
|
|
void xra(uint8_t value) {
|
|
auto& f = F();
|
|
clearFlag(f, AC | CF);
|
|
adjustSZP<Intel8080>(f, A() ^= value);
|
|
}
|
|
|
|
void add(uint8_t value, int carry = 0) {
|
|
auto& a = A();
|
|
auto& f = F();
|
|
register16_t sum;
|
|
sum.word = a + value + carry;
|
|
adjustAuxiliaryCarryAdd(f, a, value, sum.word);
|
|
a = sum.low;
|
|
setFlag(f, CF, sum.word & Bit8);
|
|
adjustSZP<Intel8080>(f, a);
|
|
}
|
|
|
|
void adc(uint8_t value) {
|
|
add(value, F() & CF);
|
|
}
|
|
|
|
void dad(uint16_t value) {
|
|
auto& f = F();
|
|
auto sum = HL().word + value;
|
|
setFlag(f, CF, sum & Bit16);
|
|
HL().word = sum;
|
|
}
|
|
|
|
void sub(uint8_t& operand, uint8_t value, int carry = 0) {
|
|
auto& f = F();
|
|
register16_t difference;
|
|
difference.word = operand - value - carry;
|
|
adjustAuxiliaryCarrySub(f, operand, value, difference.word);
|
|
operand = difference.low;
|
|
setFlag(f, CF, difference.word & Bit8);
|
|
adjustSZP<Intel8080>(f, operand);
|
|
}
|
|
|
|
void sub(uint8_t value, int carry = 0) {
|
|
sub(A(), value, carry);
|
|
}
|
|
|
|
void sbb(uint8_t value) {
|
|
sub(value, F() & CF);
|
|
}
|
|
|
|
void mov_m_r(uint8_t value) {
|
|
m_memory.ADDRESS() = HL();
|
|
m_memory.reference() = value;
|
|
}
|
|
|
|
uint8_t mov_r_m() {
|
|
m_memory.ADDRESS() = HL();
|
|
return m_memory.reference();
|
|
}
|
|
|
|
//
|
|
|
|
void ___();
|
|
|
|
// Move, load, and store
|
|
|
|
void mov_a_a() { }
|
|
void mov_a_b() { A() = B(); }
|
|
void mov_a_c() { A() = C(); }
|
|
void mov_a_d() { A() = D(); }
|
|
void mov_a_e() { A() = E(); }
|
|
void mov_a_h() { A() = H(); }
|
|
void mov_a_l() { A() = L(); }
|
|
|
|
void mov_b_a() { B() = A(); }
|
|
void mov_b_b() { }
|
|
void mov_b_c() { B() = C(); }
|
|
void mov_b_d() { B() = D(); }
|
|
void mov_b_e() { B() = E(); }
|
|
void mov_b_h() { B() = H(); }
|
|
void mov_b_l() { B() = L(); }
|
|
|
|
void mov_c_a() { C() = A(); }
|
|
void mov_c_b() { C() = B(); }
|
|
void mov_c_c() { }
|
|
void mov_c_d() { C() = D(); }
|
|
void mov_c_e() { C() = E(); }
|
|
void mov_c_h() { C() = H(); }
|
|
void mov_c_l() { C() = L(); }
|
|
|
|
void mov_d_a() { D() = A(); }
|
|
void mov_d_b() { D() = B(); }
|
|
void mov_d_c() { D() = C(); }
|
|
void mov_d_d() { }
|
|
void mov_d_e() { D() = E(); }
|
|
void mov_d_h() { D() = H(); }
|
|
void mov_d_l() { D() = L(); }
|
|
|
|
void mov_e_a() { E() = A(); }
|
|
void mov_e_b() { E() = B(); }
|
|
void mov_e_c() { E() = C(); }
|
|
void mov_e_d() { E() = D(); }
|
|
void mov_e_e() { }
|
|
void mov_e_h() { E() = H(); }
|
|
void mov_e_l() { E() = L(); }
|
|
|
|
void mov_h_a() { H() = A(); }
|
|
void mov_h_b() { H() = B(); }
|
|
void mov_h_c() { H() = C(); }
|
|
void mov_h_d() { H() = D(); }
|
|
void mov_h_e() { H() = E(); }
|
|
void mov_h_h() { }
|
|
void mov_h_l() { H() = L(); }
|
|
|
|
void mov_l_a() { L() = A(); }
|
|
void mov_l_b() { L() = B(); }
|
|
void mov_l_c() { L() = C(); }
|
|
void mov_l_d() { L() = D(); }
|
|
void mov_l_e() { L() = E(); }
|
|
void mov_l_h() { L() = H(); }
|
|
void mov_l_l() { }
|
|
|
|
void mov_m_a() { mov_m_r(A()); }
|
|
void mov_m_b() { mov_m_r(B()); }
|
|
void mov_m_c() { mov_m_r(C()); }
|
|
void mov_m_d() { mov_m_r(D()); }
|
|
void mov_m_e() { mov_m_r(E()); }
|
|
void mov_m_h() { mov_m_r(H()); }
|
|
void mov_m_l() { mov_m_r(L()); }
|
|
|
|
void mov_a_m() { A() = mov_r_m(); }
|
|
void mov_b_m() { B() = mov_r_m(); }
|
|
void mov_c_m() { C() = mov_r_m(); }
|
|
void mov_d_m() { D() = mov_r_m(); }
|
|
void mov_e_m() { E() = mov_r_m(); }
|
|
void mov_h_m() { H() = mov_r_m(); }
|
|
void mov_l_m() { L() = mov_r_m(); }
|
|
|
|
void mvi_a() { A() = fetchByte(); }
|
|
void mvi_b() { B() = fetchByte(); }
|
|
void mvi_c() { C() = fetchByte(); }
|
|
void mvi_d() { D() = fetchByte(); }
|
|
void mvi_e() { E() = fetchByte(); }
|
|
void mvi_h() { H() = fetchByte(); }
|
|
void mvi_l() { L() = fetchByte(); }
|
|
|
|
void mvi_m() {
|
|
auto data = fetchByte();
|
|
m_memory.ADDRESS() = HL();
|
|
m_memory.reference() = data;
|
|
}
|
|
|
|
void lxi_b() { Processor::fetchWord(BC()); }
|
|
void lxi_d() { Processor::fetchWord(DE()); }
|
|
void lxi_h() { Processor::fetchWord(HL()); }
|
|
|
|
void stax_r(register16_t& destination) {
|
|
m_memory.ADDRESS() = destination;
|
|
m_memory.reference() = A();
|
|
}
|
|
|
|
void stax_b() { stax_r(BC()); }
|
|
void stax_d() { stax_r(DE()); }
|
|
|
|
void ldax_r(register16_t& source) {
|
|
m_memory.ADDRESS() = source;
|
|
A() = m_memory.reference();
|
|
}
|
|
|
|
void ldax_b() { ldax_r(BC()); }
|
|
void ldax_d() { ldax_r(DE()); }
|
|
|
|
void sta() {
|
|
fetchWord();
|
|
memptrReference() = A();
|
|
}
|
|
|
|
void lda() {
|
|
fetchWord();
|
|
A() = memptrReference();
|
|
}
|
|
|
|
void shld() {
|
|
fetchWord();
|
|
setWordViaMemptr(HL());
|
|
}
|
|
|
|
void lhld() {
|
|
fetchWord();
|
|
getWordViaMemptr(HL());
|
|
}
|
|
|
|
void xchg() {
|
|
std::swap(DE(), HL());
|
|
}
|
|
|
|
// stack ops
|
|
|
|
void push_b() { pushWord(BC()); }
|
|
void push_d() { pushWord(DE()); }
|
|
void push_h() { pushWord(HL()); }
|
|
void push_psw() { pushWord(AF()); }
|
|
|
|
void pop_b() { popWord(BC()); }
|
|
void pop_d() { popWord(DE()); }
|
|
void pop_h() { popWord(HL()); }
|
|
|
|
void pop_psw() {
|
|
popWord(AF());
|
|
adjustReservedFlags();
|
|
}
|
|
|
|
void xhtl() {
|
|
m_memory.ADDRESS() = SP();
|
|
MEMPTR().low = m_memory.reference();
|
|
m_memory.reference() = L();
|
|
L() = MEMPTR().low;
|
|
m_memory.ADDRESS().word++;
|
|
MEMPTR().high = m_memory.reference();
|
|
m_memory.reference() = H();
|
|
H() = MEMPTR().high;
|
|
}
|
|
|
|
void sphl() {
|
|
SP() = HL();
|
|
}
|
|
|
|
void lxi_sp() {
|
|
Processor::fetchWord(SP());
|
|
}
|
|
|
|
void inx_sp() { ++SP().word; }
|
|
void dcx_sp() { --SP().word; }
|
|
|
|
// jump
|
|
|
|
void jmp() { jumpConditional(true); }
|
|
|
|
void jc() { jumpConditional(F() & CF); }
|
|
void jnc() { jumpConditional(!(F() & CF)); }
|
|
|
|
void jz() { jumpConditional(F() & ZF); }
|
|
void jnz() { jumpConditional(!(F() & ZF)); }
|
|
|
|
void jpe() { jumpConditional(F() & PF); }
|
|
void jpo() { jumpConditional(!(F() & PF)); }
|
|
|
|
void jm() { jumpConditional(F() & SF); }
|
|
void jp() { jumpConditional(!(F() & SF)); }
|
|
|
|
void pchl() {
|
|
PC() = HL();
|
|
}
|
|
|
|
// call
|
|
|
|
void callDirect() {
|
|
fetchWord();
|
|
call();
|
|
}
|
|
|
|
void cc() { if (callConditional(F() & CF)) cycles += 6; }
|
|
void cnc() { if (callConditional(!(F() & CF))) cycles += 6; }
|
|
|
|
void cpe() { if (callConditional(F() & PF)) cycles += 6; }
|
|
void cpo() { if (callConditional(!(F() & PF))) cycles += 6; }
|
|
|
|
void cz() { if (callConditional(F() & ZF)) cycles += 6; }
|
|
void cnz() { if (callConditional(!(F() & ZF))) cycles += 6; }
|
|
|
|
void cm() { if (callConditional(F() & SF)) cycles += 6; }
|
|
void cp() { if (callConditional(!(F() & SF))) cycles += 6; }
|
|
|
|
// return
|
|
|
|
void rc() { if (returnConditional(F() & CF)) cycles += 6; }
|
|
void rnc() { if (returnConditional(!(F() & CF))) cycles += 6; }
|
|
|
|
void rz() { if (returnConditional(F() & ZF)) cycles += 6; }
|
|
void rnz() { if (returnConditional(!(F() & ZF))) cycles += 6; }
|
|
|
|
void rpe() { if (returnConditional(F() & PF)) cycles += 6; }
|
|
void rpo() { if (returnConditional(!(F() & PF))) cycles += 6; }
|
|
|
|
void rm() { if (returnConditional(F() & SF)) cycles += 6; }
|
|
void rp() { if (returnConditional(!(F() & SF))) cycles += 6; }
|
|
|
|
// restart
|
|
|
|
void rst_0() { restart(0 << 3); }
|
|
void rst_1() { restart(1 << 3); }
|
|
void rst_2() { restart(2 << 3); }
|
|
void rst_3() { restart(3 << 3); }
|
|
void rst_4() { restart(4 << 3); }
|
|
void rst_5() { restart(5 << 3); }
|
|
void rst_6() { restart(6 << 3); }
|
|
void rst_7() { restart(7 << 3); }
|
|
|
|
// increment and decrement
|
|
|
|
void inr_a() { postIncrement(F(), ++A()); }
|
|
void inr_b() { postIncrement(F(), ++B()); }
|
|
void inr_c() { postIncrement(F(), ++C()); }
|
|
void inr_d() { postIncrement(F(), ++D()); }
|
|
void inr_e() { postIncrement(F(), ++E()); }
|
|
void inr_h() { postIncrement(F(), ++H()); }
|
|
void inr_l() { postIncrement(F(), ++L()); }
|
|
|
|
void inr_m() {
|
|
m_memory.ADDRESS() = HL();
|
|
auto value = m_memory.reference();
|
|
postIncrement(F(), ++value);
|
|
m_memory.reference() = value;
|
|
}
|
|
|
|
void dcr_a() { postDecrement(F(), --A()); }
|
|
void dcr_b() { postDecrement(F(), --B()); }
|
|
void dcr_c() { postDecrement(F(), --C()); }
|
|
void dcr_d() { postDecrement(F(), --D()); }
|
|
void dcr_e() { postDecrement(F(), --E()); }
|
|
void dcr_h() { postDecrement(F(), --H()); }
|
|
void dcr_l() { postDecrement(F(), --L()); }
|
|
|
|
void dcr_m() {
|
|
m_memory.ADDRESS() = HL();
|
|
auto value = m_memory.reference();
|
|
postDecrement(F(), --value);
|
|
m_memory.reference() = value;
|
|
}
|
|
|
|
void inx_b() { ++BC().word; }
|
|
void inx_d() { ++DE().word; }
|
|
void inx_h() { ++HL().word; }
|
|
|
|
void dcx_b() { --BC().word; }
|
|
void dcx_d() { --DE().word; }
|
|
void dcx_h() { --HL().word; }
|
|
|
|
// add
|
|
|
|
void add_a() { add(A()); }
|
|
void add_b() { add(B()); }
|
|
void add_c() { add(C()); }
|
|
void add_d() { add(D()); }
|
|
void add_e() { add(E()); }
|
|
void add_h() { add(H()); }
|
|
void add_l() { add(L()); }
|
|
|
|
void add_m() {
|
|
m_memory.ADDRESS() = HL();
|
|
add(m_memory.reference());
|
|
}
|
|
|
|
void adi() { add(fetchByte()); }
|
|
|
|
void adc_a() { adc(A()); }
|
|
void adc_b() { adc(B()); }
|
|
void adc_c() { adc(C()); }
|
|
void adc_d() { adc(D()); }
|
|
void adc_e() { adc(E()); }
|
|
void adc_h() { adc(H()); }
|
|
void adc_l() { adc(L()); }
|
|
|
|
void adc_m() {
|
|
m_memory.ADDRESS() = HL();
|
|
adc(m_memory.reference());
|
|
}
|
|
|
|
void aci() { adc(fetchByte()); }
|
|
|
|
void dad_b() { dad(BC().word); }
|
|
void dad_d() { dad(DE().word); }
|
|
void dad_h() { dad(HL().word); }
|
|
void dad_sp() { dad(SP().word); }
|
|
|
|
// subtract
|
|
|
|
void sub_a() { sub(A()); }
|
|
void sub_b() { sub(B()); }
|
|
void sub_c() { sub(C()); }
|
|
void sub_d() { sub(D()); }
|
|
void sub_e() { sub(E()); }
|
|
void sub_h() { sub(H()); }
|
|
void sub_l() { sub(L()); }
|
|
|
|
void sub_m() {
|
|
m_memory.ADDRESS() = HL();
|
|
sub(m_memory.reference());
|
|
}
|
|
|
|
void sbb_a() { sbb(A()); }
|
|
void sbb_b() { sbb(B()); }
|
|
void sbb_c() { sbb(C()); }
|
|
void sbb_d() { sbb(D()); }
|
|
void sbb_e() { sbb(E()); }
|
|
void sbb_h() { sbb(H()); }
|
|
void sbb_l() { sbb(L()); }
|
|
|
|
void sbb_m() {
|
|
m_memory.ADDRESS() = HL();
|
|
sbb(m_memory.reference());
|
|
}
|
|
|
|
void sbi() {
|
|
sbb(fetchByte());
|
|
}
|
|
|
|
void sui() {
|
|
sub(fetchByte());
|
|
}
|
|
|
|
// logical
|
|
|
|
void ana_a() { anda(A()); }
|
|
void ana_b() { anda(B()); }
|
|
void ana_c() { anda(C()); }
|
|
void ana_d() { anda(D()); }
|
|
void ana_e() { anda(E()); }
|
|
void ana_h() { anda(H()); }
|
|
void ana_l() { anda(L()); }
|
|
|
|
void ana_m() {
|
|
m_memory.ADDRESS() = HL();
|
|
anda(m_memory.reference());
|
|
}
|
|
|
|
void ani() { anda(fetchByte()); }
|
|
|
|
void xra_a() { xra(A()); }
|
|
void xra_b() { xra(B()); }
|
|
void xra_c() { xra(C()); }
|
|
void xra_d() { xra(D()); }
|
|
void xra_e() { xra(E()); }
|
|
void xra_h() { xra(H()); }
|
|
void xra_l() { xra(L()); }
|
|
|
|
void xra_m() {
|
|
m_memory.ADDRESS() = HL();
|
|
xra(m_memory.reference());
|
|
}
|
|
|
|
void xri() { xra(fetchByte()); }
|
|
|
|
void ora_a() { ora(A()); }
|
|
void ora_b() { ora(B()); }
|
|
void ora_c() { ora(C()); }
|
|
void ora_d() { ora(D()); }
|
|
void ora_e() { ora(E()); }
|
|
void ora_h() { ora(H()); }
|
|
void ora_l() { ora(L()); }
|
|
|
|
void ora_m() {
|
|
m_memory.ADDRESS() = HL();
|
|
ora(m_memory.reference());
|
|
}
|
|
|
|
void ori() { ora(fetchByte()); }
|
|
|
|
void cmp_a() { compare(A()); }
|
|
void cmp_b() { compare(B()); }
|
|
void cmp_c() { compare(C()); }
|
|
void cmp_d() { compare(D()); }
|
|
void cmp_e() { compare(E()); }
|
|
void cmp_h() { compare(H()); }
|
|
void cmp_l() { compare(L()); }
|
|
|
|
void cmp_m() {
|
|
m_memory.ADDRESS() = HL();
|
|
compare(m_memory.reference());
|
|
}
|
|
|
|
void cpi() { compare(fetchByte()); }
|
|
|
|
// rotate
|
|
|
|
void rlc() {
|
|
auto& a = A();
|
|
auto carry = a & Bit7;
|
|
a = (a << 1) | (carry >> 7);
|
|
setFlag(F(), CF, carry);
|
|
}
|
|
|
|
void rrc() {
|
|
auto& a = A();
|
|
auto carry = a & Bit0;
|
|
a = (a >> 1) | (carry << 7);
|
|
setFlag(F(), CF, carry);
|
|
}
|
|
|
|
void ral() {
|
|
auto& a = A();
|
|
auto& f = F();
|
|
const auto carry = f & CF;
|
|
setFlag(f, CF, a & Bit7);
|
|
a = (a << 1) | carry;
|
|
}
|
|
|
|
void rar() {
|
|
auto& a = A();
|
|
auto& f = F();
|
|
const auto carry = f & CF;
|
|
setFlag(f, CF, a & Bit0);
|
|
a = (a >> 1) | (carry << 7);
|
|
}
|
|
|
|
// specials
|
|
|
|
void cma() { A() ^= Mask8; }
|
|
void stc() { setFlag(F(), CF); }
|
|
void cmc() { clearFlag(F(), CF, F() & CF); }
|
|
|
|
void daa() {
|
|
const auto& a = A();
|
|
auto& f = F();
|
|
auto carry = f & CF;
|
|
uint8_t addition = 0;
|
|
if ((f & AC) || lowNibble(a) > 9) {
|
|
addition = 0x6;
|
|
}
|
|
if ((f & CF) || highNibble(a) > 9 || (highNibble(a) >= 9 && lowNibble(a) > 9)) {
|
|
addition |= 0x60;
|
|
carry = true;
|
|
}
|
|
add(addition);
|
|
setFlag(f, CF, carry);
|
|
}
|
|
|
|
// input/output
|
|
|
|
void out() { m_ports.write(fetchByte(), A()); }
|
|
void in() { A() = m_ports.read(fetchByte()); }
|
|
|
|
// control
|
|
|
|
void ei() { m_interrupt = true; }
|
|
void di() { m_interrupt = false; }
|
|
|
|
void nop() {}
|
|
|
|
void hlt() { halt(); }
|
|
};
|
|
} |