// // Z80.hpp // Clock Signal // // Created by Thomas Harte on 14/05/2017. // Copyright © 2017 Thomas Harte. All rights reserved. // #ifndef Z80_hpp #define Z80_hpp #include #include #include #include "../MicroOpScheduler.hpp" #include "../RegisterSizes.hpp" namespace CPU { namespace Z80 { /* The list of registers that can be accessed via @c set_value_of_register and @c set_value_of_register. */ enum Register { ProgramCounter, StackPointer, A, Flags, AF, B, C, BC, D, E, DE, H, L, HL, ADash, FlagsDash, AFDash, BDash, CDash, BCDash, DDash, EDash, DEDash, HDash, LDash, HLDash, IXh, IXl, IX, IYh, IYl, IY, R, I, IFF1, IFF2, IM }; /* Flags as defined on the Z80; can be used to decode the result of @c get_flags or to form a value for @c set_flags. */ enum Flag: uint8_t { Sign = 0x80, Zero = 0x40, Bit5 = 0x20, HalfCarry = 0x10, Bit3 = 0x08, Parity = 0x04, Overflow = 0x04, Subtract = 0x02, Carry = 0x01 }; /*! Subclasses will be given the task of performing bus operations, allowing them to provide whatever interface they like between a Z80 and the rest of the system. @c BusOperation lists the types of bus operation that may be requested. @c None is reserved for internal use. It will never be requested from a subclass. */ enum BusOperation { ReadOpcode = 0, Read, Write, Input, Output, Interrupt, // BusRequest, BusAcknowledge, Internal }; struct MachineCycle { BusOperation operation; int length; uint16_t *address; uint8_t *value; }; struct MicroOp { enum Type { BusOperation, DecodeOperation, MoveToNextProgram, Increment8, Increment16, Decrement8, Decrement16, Move8, Move16, AssembleAF, DisassembleAF, And, Or, Xor, TestNZ, TestZ, TestNC, TestC, TestPO, TestPE, TestP, TestM, ADD16, ADC16, SBC16, CP8, SUB8, SBC8, ADD8, ADC8, NEG, ExDEHL, ExAFAFDash, EXX, EI, DI, IM, LDI, LDIR, LDD, LDDR, CPI, CPIR, CPD, CPDR, INI, INIR, IND, INDR, OUTI, OUTIR, OUTD, OUTDR, RLA, RLCA, RRA, RRCA, RLC, RRC, RL, RR, SLA, SRA, SLL, SRL, RLD, RRD, SetInstructionPage, CalculateIndexAddress, RETN, DJNZ, DAA, CPL, SCF, CCF, RES, BIT, SET, CalculateRSTDestination, SetAFlags, SetInFlags, SetZero, IndexedPlaceHolder, None }; Type type; void *source; void *destination; MachineCycle machine_cycle; }; /*! @abstact An abstract base class for emulation of a 6502 processor via the curiously recurring template pattern/f-bounded polymorphism. @discussion Subclasses should implement @c perform_bus_operation(BusOperation operation, uint16_t address, uint8_t *value) in order to provide the bus on which the 6502 operates and @c flush(), which is called upon completion of a continuous run of cycles to allow a subclass to bring any on-demand activities up to date. Additional functionality can be provided by the host machine by providing a jam handler and inserting jam opcodes where appropriate; that will cause call outs when the program counter reaches those addresses. @c return_from_subroutine can be used to exit from a jammed state. */ template class Processor: public MicroOpScheduler { private: uint8_t a_, i_, r_; RegisterPair bc_, de_, hl_; RegisterPair afDash_, bcDash_, deDash_, hlDash_; RegisterPair ix_, iy_, pc_, sp_; bool iff1_, iff2_; int interrupt_mode_; uint8_t sign_result_, zero_result_, bit5_result_, half_carry_flag_, bit3_result_, parity_overflow_flag_, subtract_flag_, carry_flag_; int number_of_cycles_; uint8_t operation_; RegisterPair temp16_; uint8_t temp8_; struct InstructionPage { MicroOp *instructions[256]; MicroOp *all_operations; MicroOp *fetch_decode_execute; bool increments_r; InstructionPage() : all_operations(nullptr), increments_r(true), fetch_decode_execute(nullptr) { for(int c = 0; c < 256; c++) { instructions[c] = nullptr; } } ~InstructionPage() { delete[] all_operations; delete[] fetch_decode_execute; } }; InstructionPage *current_instruction_page_; InstructionPage base_page_; InstructionPage ed_page_; InstructionPage fd_page_; InstructionPage dd_page_; InstructionPage cb_page_; InstructionPage fdcb_page_; InstructionPage ddcb_page_; #define XX Program({MicroOp::None}) #define INDEX() {MicroOp::IndexedPlaceHolder}, FETCH(temp8_, pc_), WAIT(5), {MicroOp::CalculateIndexAddress, &index} #define FINDEX() {MicroOp::IndexedPlaceHolder}, FETCH(temp8_, pc_), {MicroOp::CalculateIndexAddress, &index} #define INDEX_ADDR() (add_offsets ? temp16_ : index) /// Fetches into x from address y, and then increments y. #define FETCH(x, y) {MicroOp::BusOperation, nullptr, nullptr, {Read, 3, &y.full, &x}}, {MicroOp::Increment16, &y.full} /// Fetches into x from address y. #define FETCHL(x, y) {MicroOp::BusOperation, nullptr, nullptr, {Read, 3, &y.full, &x}} /// Stores x to address y, and then increments y. #define STORE(x, y) {MicroOp::BusOperation, nullptr, nullptr, {Write, 3, &y.full, &x}}, {MicroOp::Increment16, &y.full} /// Stores x to address y. #define STOREL(x, y) {MicroOp::BusOperation, nullptr, nullptr, {Write, 3, &y.full, &x}} /// Fetches the 16-bit quantity x from address y, incrementing y twice. #define FETCH16(x, y) FETCH(x.bytes.low, y), FETCH(x.bytes.high, y) /// Fetches the 16-bit quantity x from address y, incrementing y once. #define FETCH16L(x, y) FETCH(x.bytes.low, y), FETCHL(x.bytes.high, y) /// Stores the 16-bit quantity x to address y, incrementing y once. #define STORE16L(x, y) STORE(x.bytes.low, y), STOREL(x.bytes.high, y) /// Outputs the 8-bit value to the 16-bit port #define OUT(port, value) {MicroOp::BusOperation, nullptr, nullptr, {Output, 4, &port.full, &value}} /// Inputs the 8-bit value from the 16-bit port #define IN(port, value) {MicroOp::BusOperation, nullptr, nullptr, {Input, 4, &port.full, &value}} #define PUSH(x) {MicroOp::Decrement16, &sp_.full}, STOREL(x.bytes.high, sp_), {MicroOp::Decrement16, &sp_.full}, STOREL(x.bytes.low, sp_) #define POP(x) FETCHL(x.bytes.low, sp_), {MicroOp::Increment16, &sp_.full}, FETCHL(x.bytes.high, sp_), {MicroOp::Increment16, &sp_.full} #define JP(cc) Program(FETCH16(temp16_, pc_), {MicroOp::cc}, {MicroOp::Move16, &temp16_.full, &pc_.full}) #define CALL(cc) Program(FETCH16(temp16_, pc_), {MicroOp::cc}, WAIT(1), PUSH(pc_), {MicroOp::Move16, &temp16_.full, &pc_.full}) #define RET(cc) Program(WAIT(1), {MicroOp::cc}, POP(pc_)) #define JR(cc) Program(FETCH(temp8_, pc_), {MicroOp::cc}, WAIT(5), {MicroOp::CalculateIndexAddress, &pc_.full}, {MicroOp::Move16, &temp16_.full, &pc_.full}) #define RST() Program(WAIT(1), {MicroOp::CalculateRSTDestination}, PUSH(pc_), {MicroOp::Move16, &temp16_.full, &pc_.full}) #define LD(a, b) Program({MicroOp::Move8, &b, &a}) #define LD_GROUP(r, ri) \ LD(r, bc_.bytes.high), LD(r, bc_.bytes.low), LD(r, de_.bytes.high), LD(r, de_.bytes.low), \ LD(r, index.bytes.high), LD(r, index.bytes.low), Program(INDEX(), FETCHL(ri, INDEX_ADDR())), LD(r, a_) #define READ_OP_GROUP(op) \ Program({MicroOp::op, &bc_.bytes.high}), Program({MicroOp::op, &bc_.bytes.low}), \ Program({MicroOp::op, &de_.bytes.high}), Program({MicroOp::op, &de_.bytes.low}), \ Program({MicroOp::op, &index.bytes.high}), Program({MicroOp::op, &index.bytes.low}), \ Program(INDEX(), FETCHL(temp8_, INDEX_ADDR()), {MicroOp::op, &temp8_}), \ Program({MicroOp::op, &a_}) #define RMW(x, op, ...) Program(INDEX(), FETCHL(x, INDEX_ADDR()), {MicroOp::op, &x}, WAIT(1), STOREL(x, INDEX_ADDR())) #define RMWI(x, op, ...) Program(WAIT(2), FETCHL(x, INDEX_ADDR()), {MicroOp::op, &x}, WAIT(1), STOREL(x, INDEX_ADDR())) #define MODIFY_OP_GROUP(op) \ Program({MicroOp::op, &bc_.bytes.high}), Program({MicroOp::op, &bc_.bytes.low}), \ Program({MicroOp::op, &de_.bytes.high}), Program({MicroOp::op, &de_.bytes.low}), \ Program({MicroOp::op, &index.bytes.high}), Program({MicroOp::op, &index.bytes.low}), \ RMW(temp8_, op), \ Program({MicroOp::op, &a_}) #define IX_MODIFY_OP_GROUP(op) \ RMWI(bc_.bytes.high, op), \ RMWI(bc_.bytes.low, op), \ RMWI(de_.bytes.high, op), \ RMWI(de_.bytes.low, op), \ RMWI(hl_.bytes.high, op), \ RMWI(hl_.bytes.low, op), \ RMWI(temp8_, op), \ RMWI(a_, op) #define IX_READ_OP_GROUP(op) \ Program(WAIT(2), FETCHL(temp8_, INDEX_ADDR()), {MicroOp::op, &temp8_}, WAIT(1)), \ Program(WAIT(2), FETCHL(temp8_, INDEX_ADDR()), {MicroOp::op, &temp8_}, WAIT(1)), \ Program(WAIT(2), FETCHL(temp8_, INDEX_ADDR()), {MicroOp::op, &temp8_}, WAIT(1)), \ Program(WAIT(2), FETCHL(temp8_, INDEX_ADDR()), {MicroOp::op, &temp8_}, WAIT(1)), \ Program(WAIT(2), FETCHL(temp8_, INDEX_ADDR()), {MicroOp::op, &temp8_}, WAIT(1)), \ Program(WAIT(2), FETCHL(temp8_, INDEX_ADDR()), {MicroOp::op, &temp8_}, WAIT(1)), \ Program(WAIT(2), FETCHL(temp8_, INDEX_ADDR()), {MicroOp::op, &temp8_}, WAIT(1)), \ Program(WAIT(2), FETCHL(temp8_, INDEX_ADDR()), {MicroOp::op, &temp8_}, WAIT(1)) #define ADD16(d, s) Program(WAIT(4), WAIT(3), {MicroOp::ADD16, &s.full, &d.full}) #define ADC16(d, s) Program(WAIT(4), WAIT(3), {MicroOp::ADC16, &s.full, &d.full}) #define SBC16(d, s) Program(WAIT(4), WAIT(3), {MicroOp::SBC16, &s.full, &d.full}) #define WAIT(n) {MicroOp::BusOperation, nullptr, nullptr, {Internal, n} } #define Program(...) { __VA_ARGS__, {MicroOp::MoveToNextProgram} } typedef MicroOp InstructionTable[256][20]; void assemble_page(InstructionPage &target, InstructionTable &table, bool add_offsets) { size_t number_of_micro_ops = 0; size_t lengths[256]; // Count number of micro-ops required. for(int c = 0; c < 256; c++) { size_t length = 0; while(table[c][length].type != MicroOp::MoveToNextProgram && table[c][length].type != MicroOp::None) length++; length++; lengths[c] = length; number_of_micro_ops += length; } // Allocate a landing area. target.all_operations = new MicroOp[number_of_micro_ops]; // Copy in all programs and set pointers. size_t destination = 0; for(int c = 0; c < 256; c++) { target.instructions[c] = &target.all_operations[destination]; for(int t = 0; t < lengths[c];) { // If an index placeholder is hit then drop it, and if offsets aren't being added, // then also drop the indexing that follows, which is assumed to be everything // up to and including the next ::CalculateIndexAddress. Coupled to the INDEX() macro. if(table[c][t].type == MicroOp::IndexedPlaceHolder) { t++; if(!add_offsets) { while(table[c][t].type != MicroOp::CalculateIndexAddress) t++; t++; } } target.all_operations[destination] = table[c][t]; destination++; t++; } } } void assemble_ed_page(InstructionPage &target) { #define IN_C(r) Program(IN(bc_, r), {MicroOp::SetInFlags, &r}) #define OUT_C(r) Program(OUT(bc_, r)) #define IN_OUT(r) IN_C(r), OUT_C(r) #define NOP_ROW() XX, XX, XX, XX, XX, XX, XX, XX, XX, XX, XX, XX, XX, XX, XX, XX InstructionTable ed_program_table = { NOP_ROW(), /* 0x00 */ NOP_ROW(), /* 0x10 */ NOP_ROW(), /* 0x20 */ NOP_ROW(), /* 0x30 */ /* 0x40 IN B, (C); 0x41 OUT (C), B */ IN_OUT(bc_.bytes.high), /* 0x42 SBC HL, BC */ SBC16(hl_, bc_), /* 0x43 LD (nn), BC */ Program(FETCH16(temp16_, pc_), STORE16L(bc_, temp16_)), /* 0x44 NEG */ Program({MicroOp::NEG}), /* 0x45 RETN */ Program(POP(pc_), {MicroOp::RETN}), /* 0x46 IM 0 */ Program({MicroOp::IM}), /* 0x47 LD I, A */ LD(i_, a_), /* 0x40 IN B, (C); 0x41 OUT (C), B */ IN_OUT(bc_.bytes.low), /* 0x4a ADC HL, BC */ ADC16(hl_, bc_), /* 0x4b LD BC, (nn) */ Program(FETCH16(temp16_, pc_), FETCH16L(bc_, temp16_)), /* 0x4c NEG */ Program({MicroOp::NEG}), /* 0x4d RETI */ Program(POP(pc_), {MicroOp::RETN}), /* 0x4e IM 0/1 */ Program({MicroOp::IM}), /* 0x4f LD R, A */ LD(r_, a_), /* 0x40 IN B, (C); 0x41 OUT (C), B */ IN_OUT(de_.bytes.high), /* 0x52 SBC HL, DE */ SBC16(hl_, de_), /* 0x53 LD (nn), DE */ Program(FETCH16(temp16_, pc_), STORE16L(de_, temp16_)), /* 0x54 NEG */ Program({MicroOp::NEG}), /* 0x55 RETN */ Program(POP(pc_), {MicroOp::RETN}), /* 0x56 IM 1 */ Program({MicroOp::IM}), /* 0x57 LD A, I */ Program({MicroOp::Move8, &i_, &a_}, {MicroOp::SetAFlags}), /* 0x40 IN B, (C); 0x41 OUT (C), B */ IN_OUT(de_.bytes.low), /* 0x5a ADC HL, DE */ ADC16(hl_, de_), /* 0x5b LD DE, (nn) */ Program(FETCH16(temp16_, pc_), FETCH16L(de_, temp16_)), /* 0x5c NEG */ Program({MicroOp::NEG}), /* 0x5d RETN */ Program(POP(pc_), {MicroOp::RETN}), /* 0x5e IM 2 */ Program({MicroOp::IM}), /* 0x5f LD A, R */ Program({MicroOp::Move8, &r_, &a_}, {MicroOp::SetAFlags}), /* 0x40 IN B, (C); 0x41 OUT (C), B */ IN_OUT(hl_.bytes.high), /* 0x62 SBC HL, HL */ SBC16(hl_, hl_), /* 0x63 LD (nn), HL */ Program(FETCH16(temp16_, pc_), STORE16L(hl_, temp16_)), /* 0x64 NEG */ Program({MicroOp::NEG}), /* 0x65 RETN */ Program(POP(pc_), {MicroOp::RETN}), /* 0x66 IM 0 */ Program({MicroOp::IM}), /* 0x67 RRD */ Program(FETCHL(temp8_, hl_), WAIT(4), {MicroOp::RRD}, STOREL(temp8_, hl_)), /* 0x40 IN B, (C); 0x41 OUT (C), B */ IN_OUT(hl_.bytes.low), /* 0x6a ADC HL, HL */ ADC16(hl_, hl_), /* 0x6b LD HL, (nn) */ Program(FETCH16(temp16_, pc_), FETCH16L(hl_, temp16_)), /* 0x6c NEG */ Program({MicroOp::NEG}), /* 0x6d RETN */ Program(POP(pc_), {MicroOp::RETN}), /* 0x6e IM 0/1 */ Program({MicroOp::IM}), /* 0x6f RLD */ Program(FETCHL(temp8_, hl_), WAIT(4), {MicroOp::RLD}, STOREL(temp8_, hl_)), /* 0x70 IN (C) */ IN_C(temp8_), /* 0x71 OUT (C), 0 */ Program({MicroOp::SetZero}, OUT(bc_, temp8_)), /* 0x72 SBC HL, SP */ SBC16(hl_, sp_), /* 0x73 LD (nn), SP */ Program(FETCH16(temp16_, pc_), STORE16L(sp_, temp16_)), /* 0x74 NEG */ Program({MicroOp::NEG}), /* 0x75 RETN */ Program(POP(pc_), {MicroOp::RETN}), /* 0x76 IM 1 */ Program({MicroOp::IM}), /* 0x77 XX */ XX, /* 0x40 IN B, (C); 0x41 OUT (C), B */ IN_OUT(a_), /* 0x7a ADC HL, SP */ ADC16(hl_, sp_), /* 0x7b LD SP, (nn) */ Program(FETCH16(temp16_, pc_), FETCH16L(sp_, temp16_)), /* 0x7c NEG */ Program({MicroOp::NEG}), /* 0x7d RETN */ Program(POP(pc_), {MicroOp::RETN}), /* 0x7e IM 2 */ Program({MicroOp::IM}), /* 0x7f XX */ XX, NOP_ROW(), /* 0x80 */ NOP_ROW(), /* 0x90 */ /* 0xa0 LDI */ Program(FETCHL(temp8_, hl_), STOREL(temp8_, de_), WAIT(2), {MicroOp::LDI}), /* 0xa1 CPI */ Program(FETCHL(temp8_, hl_), WAIT(5), {MicroOp::CPI}), /* 0xa2 INI */ Program(IN(bc_, temp8_), STOREL(temp8_, hl_), WAIT(1), {MicroOp::INI}), /* 0xa3 OTI */ Program(OUT(bc_, temp8_), STOREL(temp8_, hl_), WAIT(1), {MicroOp::OUTI}), XX, XX, XX, XX, /* 0xa8 LDD */ Program(FETCHL(temp8_, hl_), STOREL(temp8_, de_), WAIT(2), {MicroOp::LDD}), /* 0xa9 CPD */ Program(FETCHL(temp8_, hl_), WAIT(5), {MicroOp::CPD}), /* 0xaa IND */ Program(IN(bc_, temp8_), STOREL(temp8_, hl_), WAIT(1), {MicroOp::IND}), /* 0xab OTD */ Program(OUT(bc_, temp8_), STOREL(temp8_, hl_), WAIT(1), {MicroOp::OUTD}), XX, XX, XX, XX, /* 0xb0 LDIR */ Program(FETCHL(temp8_, hl_), STOREL(temp8_, de_), WAIT(2), {MicroOp::LDIR}, WAIT(5)), /* 0xb1 CPIR */ Program(FETCHL(temp8_, hl_), WAIT(5), {MicroOp::CPIR}, WAIT(5)), /* 0xb2 INIR */ Program(IN(bc_, temp8_), STOREL(temp8_, hl_), WAIT(1), {MicroOp::INIR}, WAIT(5)), /* 0xb3 OTIR */ Program(IN(bc_, temp8_), STOREL(temp8_, hl_), WAIT(1), {MicroOp::OUTIR}, WAIT(5)), XX, XX, XX, XX, /* 0xb8 LDDR */ Program(FETCHL(temp8_, hl_), STOREL(temp8_, de_), WAIT(2), {MicroOp::LDDR}, WAIT(5)), /* 0xb9 CPDR */ Program(FETCHL(temp8_, hl_), WAIT(5), {MicroOp::CPDR}, WAIT(5)), /* 0xba INDR */ Program(IN(bc_, temp8_), STOREL(temp8_, hl_), WAIT(1), {MicroOp::INDR}, WAIT(5)), /* 0xbb OTDR */ Program(IN(bc_, temp8_), STOREL(temp8_, hl_), WAIT(1), {MicroOp::OUTDR}, WAIT(5)), XX, XX, XX, XX, NOP_ROW(), /* 0xc0 */ NOP_ROW(), /* 0xd0 */ NOP_ROW(), /* 0xe0 */ NOP_ROW(), /* 0xf0 */ }; assemble_page(target, ed_program_table, false); #undef NOP_ROW } void assemble_cb_page(InstructionPage &target, RegisterPair &index, bool add_offsets) { #define OCTO_OP_GROUP(m, x) m(x), m(x), m(x), m(x), m(x), m(x), m(x), m(x) #define CB_PAGE(m, p) m(RLC), m(RRC), m(RL), m(RR), m(SLA), m(SRA), m(SLL), m(SRL), OCTO_OP_GROUP(p, BIT), OCTO_OP_GROUP(m, RES), OCTO_OP_GROUP(m, SET) InstructionTable cb_program_table = { /* 0x00 RLC B; 0x01 RLC C; 0x02 RLC D; 0x03 RLC E; 0x04 RLC H; 0x05 RLC L; 0x06 RLC (HL); 0x07 RLC A */ /* 0x08 RRC B; 0x09 RRC C; 0x0a RRC D; 0x0b RRC E; 0x0c RRC H; 0x0d RRC L; 0x0e RRC (HL); 0x0f RRC A */ /* 0x10 RL B; 0x11 RL C; 0x12 RL D; 0x13 RL E; 0x14 RL H; 0x15 RL L; 0x16 RL (HL); 0x17 RL A */ /* 0x18 RR B; 0x99 RR C; 0x1a RR D; 0x1b RR E; 0x1c RR H; 0x1d RR L; 0x1e RR (HL); 0x1f RR A */ /* 0x20 SLA B; 0x21 SLA C; 0x22 SLA D; 0x23 SLA E; 0x24 SLA H; 0x25 SLA L; 0x26 SLA (HL); 0x27 SLA A */ /* 0x28 SRA B; 0x29 SRA C; 0x2a SRA D; 0x2b SRA E; 0x2c SRA H; 0x2d SRA L; 0x2e SRA (HL); 0x2f SRA A */ /* 0x30 SLL B; 0x31 SLL C; 0x32 SLL D; 0x33 SLL E; 0x34 SLL H; 0x35 SLL L; 0x36 SLL (HL); 0x37 SLL A */ /* 0x38 SRL B; 0x39 SRL C; 0x3a SRL D; 0x3b SRL E; 0x3c SRL H; 0x3d SRL L; 0x3e SRL (HL); 0x3f SRL A */ /* 0x40 – 0x7f: BIT */ /* 0x80 – 0xcf: RES */ /* 0xd0 – 0xdf: SET */ CB_PAGE(MODIFY_OP_GROUP, READ_OP_GROUP) }; InstructionTable offsets_cb_program_table = { CB_PAGE(IX_MODIFY_OP_GROUP, IX_READ_OP_GROUP) }; assemble_page(target, add_offsets ? offsets_cb_program_table : cb_program_table, add_offsets); #undef OCTO_OP_GROUP #undef CB_PAGE } void assemble_base_page(InstructionPage &target, RegisterPair &index, bool add_offsets, InstructionPage &cb_page) { #define INC_DEC_LD(r) \ Program({MicroOp::Increment8, &r}), \ Program({MicroOp::Decrement8, &r}), \ Program(FETCH(r, pc_)) #define INC_INC_DEC_LD(rf, r) \ Program(WAIT(2), {MicroOp::Increment16, &rf.full}), INC_DEC_LD(r) #define DEC_INC_DEC_LD(rf, r) \ Program(WAIT(2), {MicroOp::Decrement16, &rf.full}), INC_DEC_LD(r) InstructionTable base_program_table = { /* 0x00 NOP */ { {MicroOp::MoveToNextProgram} }, /* 0x01 LD BC, nn */ Program(FETCH16(bc_, pc_)), /* 0x02 LD (BC), A */ Program(STOREL(a_, bc_)), /* 0x03 INC BC; 0x04 INC B; 0x05 DEC B; 0x06 LD B, n */ INC_INC_DEC_LD(bc_, bc_.bytes.high), /* 0x07 RLCA */ Program({MicroOp::RLCA}), /* 0x08 EX AF, AF' */ Program({MicroOp::ExAFAFDash}), /* 0x09 ADD HL, BC */ ADD16(index, bc_), /* 0x0a LD A, (BC) */ Program(FETCHL(a_, bc_)), /* 0x0b DEC BC; 0x0c INC C; 0x0d DEC C; 0x0e LD C, n */ DEC_INC_DEC_LD(bc_, bc_.bytes.low), /* 0x0f RRCA */ Program({MicroOp::RRCA}), /* 0x10 DJNZ */ Program(WAIT(1), FETCH(temp8_, pc_), {MicroOp::DJNZ}, WAIT(5), {MicroOp::CalculateIndexAddress, &pc_.full}, {MicroOp::Move16, &temp16_.full, &pc_.full}), /* 0x11 LD DE, nn */ Program(FETCH16(de_, pc_)), /* 0x12 LD (DE), A */ Program(STOREL(a_, de_)), /* 0x13 INC DE; 0x14 INC D; 0x15 DEC D; 0x16 LD D, n */ INC_INC_DEC_LD(de_, de_.bytes.high), /* 0x17 RLA */ Program({MicroOp::RLA}), /* 0x18 JR */ Program(FETCH(temp8_, pc_), WAIT(5), {MicroOp::CalculateIndexAddress, &pc_.full}, {MicroOp::Move16, &temp16_.full, &pc_.full}), /* 0x19 ADD HL, DE */ ADD16(index, de_), /* 0x1a LD A, (DE) */ Program(FETCHL(a_, de_)), /* 0x1b DEC DE; 0x1c INC E; 0x1d DEC E; 0x1e LD E, n */ DEC_INC_DEC_LD(de_, de_.bytes.low), /* 0x1f RRA */ Program({MicroOp::RRA}), /* 0x20 JR NZ */ JR(TestNZ), /* 0x21 LD HL, nn */ Program(FETCH16(index, pc_)), /* 0x22 LD (nn), HL */ Program(FETCH16(temp16_, pc_), STORE16L(index, temp16_)), /* 0x23 INC HL; 0x24 INC H; 0x25 DEC H; 0x26 LD H, n */ INC_INC_DEC_LD(index, index.bytes.high), /* 0x27 DAA */ Program({MicroOp::DAA}), /* 0x28 JR Z */ JR(TestZ), /* 0x29 ADD HL, HL */ ADD16(index, index), /* 0x2a LD HL, (nn) */ Program(FETCH16(temp16_, pc_), FETCH16L(index, temp16_)), /* 0x2b DEC HL; 0x2c INC L; 0x2d DEC L; 0x2e LD L, n */ DEC_INC_DEC_LD(index, index.bytes.low), /* 0x2f CPL */ Program({MicroOp::CPL}), /* 0x30 JR NC */ JR(TestNC), /* 0x31 LD SP, nn */ Program(FETCH16(sp_, pc_)), /* 0x32 LD (nn), A */ Program(FETCH16(temp16_, pc_), STOREL(a_, temp16_)), /* 0x33 INC SP */ Program(WAIT(2), {MicroOp::Increment16, &sp_.full}), /* 0x34 INC (HL) */ Program(INDEX(), FETCHL(temp8_, INDEX_ADDR()), WAIT(1), {MicroOp::Increment8, &temp8_}, STOREL(temp8_, INDEX_ADDR())), /* 0x35 DEC (HL) */ Program(INDEX(), FETCHL(temp8_, INDEX_ADDR()), WAIT(1), {MicroOp::Decrement8, &temp8_}, STOREL(temp8_, INDEX_ADDR())), /* 0x36 LD (HL), n */ Program(INDEX(), FETCH(temp8_, pc_), STOREL(temp8_, INDEX_ADDR())), /* 0x37 SCF */ Program({MicroOp::SCF}), /* 0x38 JR C */ JR(TestC), /* 0x39 ADD HL, SP */ ADD16(index, sp_), /* 0x3a LD A, (nn) */ Program(FETCH16(temp16_, pc_), FETCHL(a_, temp16_)), /* 0x3b DEC SP */ Program(WAIT(2), {MicroOp::Decrement16, &sp_.full}), /* 0x3c INC A; 0x3d DEC A; 0x3e LD A, n */ INC_DEC_LD(a_), /* 0x3f CCF */ Program({MicroOp::CCF}), /* 0x40 LD B, B; 0x41 LD B, C; 0x42 LD B, D; 0x43 LD B, E; 0x44 LD B, H; 0x45 LD B, L; 0x46 LD B, (HL); 0x47 LD B, A */ LD_GROUP(bc_.bytes.high, bc_.bytes.high), /* 0x48 LD C, B; 0x49 LD C, C; 0x4a LD C, D; 0x4b LD C, E; 0x4c LD C, H; 0x4d LD C, L; 0x4e LD C, (HL); 0x4f LD C, A */ LD_GROUP(bc_.bytes.low, bc_.bytes.low), /* 0x50 LD D, B; 0x51 LD D, C; 0x52 LD D, D; 0x53 LD D, E; 0x54 LD D, H; 0x55 LD D, L; 0x56 LD D, (HL); 0x57 LD D, A */ LD_GROUP(de_.bytes.high, de_.bytes.high), /* 0x58 LD E, B; 0x59 LD E, C; 0x5a LD E, D; 0x5b LD E, E; 0x5c LD E, H; 0x5d LD E, L; 0x5e LD E, (HL); 0x5f LD E, A */ LD_GROUP(de_.bytes.low, de_.bytes.low), /* 0x60 LD H, B; 0x61 LD H, C; 0x62 LD H, D; 0x63 LD H, E; 0x64 LD H, H; 0x65 LD H, L; 0x66 LD H, (HL); 0x67 LD H, A */ LD_GROUP(index.bytes.high, hl_.bytes.high), /* 0x68 LD L, B; 0x69 LD L, C; 0x6a LD L, D; 0x6b LD L, E; 0x6c LD L, H; 0x6d LD H, L; 0x6e LD L, (HL); 0x6f LD L, A */ LD_GROUP(index.bytes.low, hl_.bytes.low), /* 0x70 LD (HL),B */ Program(INDEX(), STOREL(bc_.bytes.high, INDEX_ADDR())), /* 0x71 LD (HL), C */ Program(INDEX(), STOREL(bc_.bytes.low, INDEX_ADDR())), /* 0x72 LD (HL),D */ Program(INDEX(), STOREL(de_.bytes.high, INDEX_ADDR())), /* 0x73 LD (HL), E */ Program(INDEX(), STOREL(de_.bytes.low, INDEX_ADDR())), /* 0x74 LD (HL),H */ Program(INDEX(), STOREL(index.bytes.high, INDEX_ADDR())), /* 0x75 LD (HL), L */ Program(INDEX(), STOREL(index.bytes.low, INDEX_ADDR())), /* 0x76 HALT */ XX, /* 0x77 LD (HL), A */ Program(INDEX(), STOREL(a_, INDEX_ADDR())), /* 0x78 LD A, B; 0x79 LD A, C; 0x7a LD A, D; 0x7b LD A, E; 0x7c LD A, H; 0x7d LD A, L; 0x7e LD A, (HL); 0x7f LD A, A */ LD_GROUP(a_, a_), /* 0x80 ADD B; 0x81 ADD C; 0x82 ADD D; 0x83 ADD E; 0x84 ADD H; 0x85 ADD L; 0x86 ADD (HL); 0x87 ADD A */ READ_OP_GROUP(ADD8), /* 0x88 ADC B; 0x89 ADC C; 0x8a ADC D; 0x8b ADC E; 0x8c ADC H; 0x8d ADC L; 0x8e ADC (HL); 0x8f ADC A */ READ_OP_GROUP(ADC8), /* 0x90 SUB B; 0x91 SUB C; 0x92 SUB D; 0x93 SUB E; 0x94 SUB H; 0x95 SUB L; 0x96 SUB (HL); 0x97 SUB A */ READ_OP_GROUP(SUB8), /* 0x98 SBC B; 0x99 SBC C; 0x9a SBC D; 0x9b SBC E; 0x9c SBC H; 0x9d SBC L; 0x9e SBC (HL); 0x9f SBC A */ READ_OP_GROUP(SBC8), /* 0xa0 AND B; 0xa1 AND C; 0xa2 AND D; 0xa3 AND E; 0xa4 AND H; 0xa5 AND L; 0xa6 AND (HL); 0xa7 AND A */ READ_OP_GROUP(And), /* 0xa8 XOR B; 0xa9 XOR C; 0xaa XOR D; 0xab XOR E; 0xac XOR H; 0xad XOR L; 0xae XOR (HL); 0xaf XOR A */ READ_OP_GROUP(Xor), /* 0xb0 OR B; 0xb1 OR C; 0xb2 OR D; 0xb3 OR E; 0xb4 OR H; 0xb5 OR L; 0xb6 OR (HL); 0xb7 OR A */ READ_OP_GROUP(Or), /* 0xb8 CP B; 0xb9 CP C; 0xba CP D; 0xbb CP E; 0xbc CP H; 0xbd CP L; 0xbe CP (HL); 0xbf CP A */ READ_OP_GROUP(CP8), /* 0xc0 RET NZ */ RET(TestNZ), /* 0xc1 POP BC */ Program(POP(bc_)), /* 0xc2 JP NZ */ JP(TestNZ), /* 0xc3 JP nn */ Program(FETCH16L(temp16_, pc_), {MicroOp::Move16, &temp16_.full, &pc_.full}), /* 0xc4 CALL NZ */ CALL(TestNZ), /* 0xc5 PUSH BC */ Program(WAIT(1), PUSH(bc_)), /* 0xc6 ADD A, n */ Program(FETCH(temp8_, pc_), {MicroOp::ADD8, &temp8_}), /* 0xc7 RST 00h */ RST(), /* 0xc8 RET Z */ RET(TestZ), /* 0xc9 RET */ Program(POP(pc_)), /* 0xca JP Z */ JP(TestZ), /* 0xcb [CB page] */Program({MicroOp::SetInstructionPage, &cb_page}, FINDEX()), /* 0xcc CALL Z */ CALL(TestZ), /* 0xcd CALL */ Program(FETCH16(temp16_, pc_), WAIT(1), PUSH(pc_), {MicroOp::Move16, &temp16_.full, &pc_.full}), /* 0xce ADC A, n */ Program(FETCH(temp8_, pc_), {MicroOp::ADC8, &temp8_}), /* 0xcf RST 08h */ RST(), /* 0xd0 RET NC */ RET(TestNC), /* 0xd1 POP DE */ Program(POP(de_)), /* 0xd2 JP NC */ JP(TestNC), /* 0xd3 OUT (n), A */Program(FETCH(temp16_.bytes.low, pc_), {MicroOp::Move8, &a_, &temp16_.bytes.high}, OUT(temp16_, a_)), /* 0xd4 CALL NC */ CALL(TestNC), /* 0xd5 PUSH DE */ Program(WAIT(1), PUSH(de_)), /* 0xd6 SUB n */ Program(FETCH(temp8_, pc_), {MicroOp::SUB8, &temp8_}), /* 0xd7 RST 10h */ RST(), /* 0xd8 RET C */ RET(TestC), /* 0xd9 EXX */ Program({MicroOp::EXX}), /* 0xda JP C */ JP(TestC), /* 0xdb IN A, (n) */Program(FETCH(temp16_.bytes.low, pc_), {MicroOp::Move8, &a_, &temp16_.bytes.high}, IN(temp16_, a_)), /* 0xdc CALL C */ CALL(TestC), /* 0xdd [DD page] */Program({MicroOp::SetInstructionPage, &dd_page_}), /* 0xde SBC A, n */ Program(FETCH(temp8_, pc_), {MicroOp::SBC8, &temp8_}), /* 0xdf RST 18h */ RST(), /* 0xe0 RET PO */ RET(TestPO), /* 0xe1 POP HL */ Program(POP(index)), /* 0xe2 JP PO */ JP(TestPO), /* 0xe3 EX (SP), HL */Program(POP(temp16_), WAIT(1), PUSH(index), WAIT(2), {MicroOp::Move16, &temp16_.full, &index.full}), /* 0xe4 CALL PO */ CALL(TestPO), /* 0xe5 PUSH HL */ Program(WAIT(1), PUSH(index)), /* 0xe6 AND n */ Program(FETCH(temp8_, pc_), {MicroOp::And, &temp8_}), /* 0xe7 RST 20h */ RST(), /* 0xe8 RET PE */ RET(TestPE), /* 0xe9 JP (HL) */ Program({MicroOp::Move16, &index.full, &pc_.full}), /* 0xea JP PE */ JP(TestPE), /* 0xeb EX DE, HL */Program({MicroOp::ExDEHL}), /* 0xec CALL PE */ CALL(TestPE), /* 0xed [ED page] */Program({MicroOp::SetInstructionPage, &ed_page_}), /* 0xee XOR n */ Program(FETCH(temp8_, pc_), {MicroOp::Xor, &temp8_}), /* 0xef RST 28h */ RST(), /* 0xf0 RET p */ RET(TestP), /* 0xf1 POP AF */ Program(POP(temp16_), {MicroOp::DisassembleAF}), /* 0xf2 JP P */ JP(TestP), /* 0xf3 DI */ Program({MicroOp::DI}), /* 0xf4 CALL P */ CALL(TestP), /* 0xf5 PUSH AF */ Program(WAIT(1), {MicroOp::AssembleAF}, PUSH(temp16_)), /* 0xf6 OR n */ Program(FETCH(temp8_, pc_), {MicroOp::Or, &temp8_}), /* 0xf7 RST 30h */ RST(), /* 0xf8 RET M */ RET(TestM), /* 0xf9 LD SP, HL */Program(WAIT(2), {MicroOp::Move16, &index.full, &sp_.full}), /* 0xfa JP M */ JP(TestM), /* 0xfb EI */ Program({MicroOp::EI}), /* 0xfc CALL M */ CALL(TestM), /* 0xfd [FD page] */Program({MicroOp::SetInstructionPage, &fd_page_}), /* 0xfe CP n */ Program(FETCH(temp8_, pc_), {MicroOp::CP8, &temp8_}), /* 0xff RST 38h */ RST(), }; assemble_cb_page(cb_page, index, add_offsets); assemble_page(target, base_program_table, add_offsets); } void assemble_fetch_decode_execute(InstructionPage &target, int length) { // TODO: this can't legitimately be static and contain references to this via pc_ and operation_; // make it something else that is built at instance construction. const MicroOp fetch_decode_execute[] = { { MicroOp::BusOperation, nullptr, nullptr, {(length == 4) ? ReadOpcode : Read, length, &pc_.full, &operation_}}, { MicroOp::DecodeOperation }, { MicroOp::MoveToNextProgram } }; target.fetch_decode_execute = new MicroOp[3]; target.fetch_decode_execute[0] = fetch_decode_execute[0]; target.fetch_decode_execute[1] = fetch_decode_execute[1]; target.fetch_decode_execute[2] = fetch_decode_execute[2]; } void decode_operation(uint8_t operation) { schedule_program(current_instruction_page_->instructions[operation]); } public: Processor() : MicroOpScheduler() { assemble_base_page(base_page_, hl_, false, cb_page_); assemble_base_page(dd_page_, ix_, true, ddcb_page_); assemble_base_page(fd_page_, iy_, true, fdcb_page_); assemble_ed_page(ed_page_); fdcb_page_.increments_r = false; ddcb_page_.increments_r = false; assemble_fetch_decode_execute(base_page_, 4); assemble_fetch_decode_execute(dd_page_, 4); assemble_fetch_decode_execute(fd_page_, 4); assemble_fetch_decode_execute(ed_page_, 4); assemble_fetch_decode_execute(cb_page_, 4); assemble_fetch_decode_execute(fdcb_page_, 3); assemble_fetch_decode_execute(ddcb_page_, 3); } /*! Runs the Z80 for a supplied number of cycles. @discussion Subclasses must implement @c perform_machine_cycle(MachineCycle *cycle) . If it is a read operation then @c value will be seeded with the value 0xff. @param number_of_cycles The number of cycles to run the Z80 for. */ void run_for_cycles(int number_of_cycles) { #define checkSchedule() \ if(!scheduled_programs_[schedule_programs_read_pointer_]) {\ current_instruction_page_ = &base_page_;\ schedule_program(base_page_.fetch_decode_execute);\ } number_of_cycles_ += number_of_cycles; checkSchedule(); while(1) { const MicroOp *operation = &scheduled_programs_[schedule_programs_read_pointer_][schedule_program_program_counter_]; schedule_program_program_counter_++; #define set_parity(v) \ parity_overflow_flag_ = v^1;\ parity_overflow_flag_ ^= parity_overflow_flag_ >> 4;\ parity_overflow_flag_ ^= parity_overflow_flag_ << 2;\ parity_overflow_flag_ ^= parity_overflow_flag_ >> 1;\ parity_overflow_flag_ &= Flag::Parity; switch(operation->type) { case MicroOp::BusOperation: if(number_of_cycles_ < operation->machine_cycle.length) { schedule_program_program_counter_--; return; } number_of_cycles_ -= operation->machine_cycle.length; number_of_cycles_ -= static_cast(this)->perform_machine_cycle(&operation->machine_cycle); break; case MicroOp::MoveToNextProgram: move_to_next_program(); checkSchedule(); break; case MicroOp::DecodeOperation: if(current_instruction_page_->increments_r) r_ = (r_ & 0x80) | ((r_ + 1) & 0x7f); pc_.full++; decode_operation(operation_); break; case MicroOp::Increment16: (*(uint16_t *)operation->source)++; break; case MicroOp::Decrement16: (*(uint16_t *)operation->source)--; break; case MicroOp::Move8: *(uint8_t *)operation->destination = *(uint8_t *)operation->source; break; case MicroOp::Move16: *(uint16_t *)operation->destination = *(uint16_t *)operation->source; break; case MicroOp::AssembleAF: temp16_.bytes.high = a_; temp16_.bytes.low = get_flags(); break; case MicroOp::DisassembleAF: a_ = temp16_.bytes.high; set_flags(temp16_.bytes.low); break; #pragma mark - Logical #define set_logical_flags(hf) \ sign_result_ = zero_result_ = bit5_result_ = bit3_result_ = a_; \ set_parity(a_); \ half_carry_flag_ = hf; \ subtract_flag_ = 0; \ carry_flag_ = 0; case MicroOp::And: a_ &= *(uint8_t *)operation->source; set_logical_flags(Flag::HalfCarry); break; case MicroOp::Or: a_ |= *(uint8_t *)operation->source; set_logical_flags(0); break; case MicroOp::Xor: a_ ^= *(uint8_t *)operation->source; set_logical_flags(0); break; #undef set_logical_flags case MicroOp::CPL: a_ ^= 0xff; subtract_flag_ = Flag::Subtract; half_carry_flag_ = Flag::HalfCarry; bit5_result_ = bit3_result_ = a_; break; case MicroOp::CCF: half_carry_flag_ = carry_flag_ << 4; carry_flag_ ^= Flag::Carry; subtract_flag_ = 0; bit5_result_ = bit3_result_ = a_; break; case MicroOp::SCF: carry_flag_ = Flag::Carry; half_carry_flag_ = 0; subtract_flag_ = 0; bit5_result_ = bit3_result_ = a_; break; #pragma mark - Flow control case MicroOp::DJNZ: bc_.bytes.high--; if(!bc_.bytes.high) { move_to_next_program(); checkSchedule(); } break; case MicroOp::CalculateRSTDestination: temp16_.full = operation_ & 0x38; break; #pragma mark - 8-bit arithmetic case MicroOp::CP8: { uint8_t value = *(uint8_t *)operation->source; int result = a_ - value; int halfResult = (a_&0xf) - (value&0xf); // overflow for a subtraction is when the signs were originally // different and the result is different again int overflow = (value^a_) & (result^a_); sign_result_ = // set sign and zero zero_result_ = (uint8_t)result; bit3_result_ = bit5_result_ = value; // set the 5 and 3 flags, which come // from the operand atypically carry_flag_ = (result >> 8) & Flag::Carry; half_carry_flag_ = halfResult & Flag::HalfCarry; parity_overflow_flag_ = (overflow&0x80) >> 5; subtract_flag_ = Flag::Subtract; } break; case MicroOp::SUB8: { uint8_t value = *(uint8_t *)operation->source; int result = a_ - value; int halfResult = (a_&0xf) - (value&0xf); // overflow for a subtraction is when the signs were originally // different and the result is different again int overflow = (value^a_) & (result^a_); a_ = (uint8_t)result; sign_result_ = zero_result_ = bit5_result_ = bit3_result_ = (uint8_t)result; carry_flag_ = (result >> 8) & Flag::Carry; half_carry_flag_ = halfResult & Flag::HalfCarry; parity_overflow_flag_ = (overflow&0x80) >> 5; subtract_flag_ = Flag::Subtract; } break; case MicroOp::SBC8: { uint8_t value = *(uint8_t *)operation->source; int result = a_ - value - carry_flag_; int halfResult = (a_&0xf) - (value&0xf) - carry_flag_; // overflow for a subtraction is when the signs were originally // different and the result is different again int overflow = (value^a_) & (result^a_); a_ = (uint8_t)result; sign_result_ = zero_result_ = bit5_result_ = bit3_result_ = (uint8_t)result; carry_flag_ = (result >> 8) & Flag::Carry; half_carry_flag_ = halfResult & Flag::HalfCarry; parity_overflow_flag_ = (overflow&0x80) >> 5; subtract_flag_ = Flag::Subtract; } break; case MicroOp::ADD8: { uint8_t value = *(uint8_t *)operation->source; int result = a_ + value; int halfResult = (a_&0xf) + (value&0xf); // overflow for addition is when the signs were originally // the same and the result is different int overflow = ~(value^a_) & (result^a_); a_ = (uint8_t)result; sign_result_ = zero_result_ = bit3_result_ = bit5_result_ = (uint8_t)result; carry_flag_ = (result >> 8) & Flag::Carry; half_carry_flag_ = halfResult & Flag::HalfCarry; parity_overflow_flag_ = (overflow&0x80) >> 5; subtract_flag_ = 0; } break; case MicroOp::ADC8: { uint8_t value = *(uint8_t *)operation->source; int result = a_ + value + carry_flag_; int halfResult = (a_&0xf) + (value&0xf) + carry_flag_; // overflow for addition is when the signs were originally // the same and the result is different int overflow = ~(value^a_) & (result^a_); a_ = (uint8_t)result; sign_result_ = zero_result_ = bit5_result_ = bit3_result_ = (uint8_t)result; carry_flag_ = (result >> 8) & Flag::Carry; half_carry_flag_ = halfResult & Flag::HalfCarry; parity_overflow_flag_ = (overflow&0x80) >> 5; subtract_flag_ = 0; } break; case MicroOp::NEG: { int overflow = (a_ == 0x80); int result = -a_; int halfResult = -(a_&0xf); a_ = (uint8_t)result; bit5_result_ = bit3_result_ = sign_result_ = zero_result_ = a_; parity_overflow_flag_ = overflow ? Flag::Overflow : 0; subtract_flag_ = Flag::Subtract; carry_flag_ = (result >> 8) & Flag::Carry; half_carry_flag_ = halfResult & Flag::HalfCarry; } break; case MicroOp::Increment8: { uint8_t value = *(uint8_t *)operation->source; int result = value + 1; // with an increment, overflow occurs if the sign changes from // positive to negative int overflow = (value ^ result) & ~value; int half_result = (value&0xf) + 1; *(uint8_t *)operation->source = (uint8_t)result; // sign, zero and 5 & 3 are set directly from the result bit5_result_ = bit3_result_ = sign_result_ = zero_result_ = (uint8_t)result; half_carry_flag_ = half_result & Flag::HalfCarry; parity_overflow_flag_ = (overflow >> 5)&Flag::Overflow; subtract_flag_ = 0; } break; case MicroOp::Decrement8: { uint8_t value = *(uint8_t *)operation->source; int result = value - 1; // with a decrement, overflow occurs if the sign changes from // negative to positive int overflow = (value ^ result) & value; int half_result = (value&0xf) - 1; *(uint8_t *)operation->source = (uint8_t)result; // sign, zero and 5 & 3 are set directly from the result bit5_result_ = bit3_result_ = sign_result_ = zero_result_ = (uint8_t)result; half_carry_flag_ = half_result & Flag::HalfCarry; parity_overflow_flag_ = (overflow >> 5)&Flag::Overflow; subtract_flag_ = Flag::Subtract; } break; case MicroOp::DAA: { int lowNibble = a_ & 0xf; int highNibble = a_ >> 4; int amountToAdd = 0; if(carry_flag_) { amountToAdd = (lowNibble > 0x9 || half_carry_flag_) ? 0x66 : 0x60; } else { if(half_carry_flag_) { if(lowNibble > 0x9) amountToAdd = (highNibble > 0x8) ? 0x66 : 0x06; else amountToAdd = (highNibble > 0x9) ? 0x66 : 0x06; } else { if(lowNibble > 0x9) amountToAdd = (highNibble > 0x8) ? 0x66 : 0x06; else amountToAdd = (highNibble > 0x9) ? 0x60 : 0x00; } } if(!carry_flag_) { if(lowNibble > 0x9) { if(highNibble > 0x8) carry_flag_ = Flag::Carry; } else { if(highNibble > 0x9) carry_flag_ = Flag::Carry; } } if(subtract_flag_) { a_ -= amountToAdd; half_carry_flag_ = (half_carry_flag_ && lowNibble < 0x6) ? Flag::HalfCarry : 0; } else { a_ += amountToAdd; half_carry_flag_ = (lowNibble > 0x9) ? Flag::HalfCarry : 0; } sign_result_ = zero_result_ = bit3_result_ = bit5_result_ = a_; set_parity(a_); } break; #pragma mark - 16-bit arithmetic case MicroOp::ADD16: { uint16_t sourceValue = *(uint16_t *)operation->source; uint16_t destinationValue = *(uint16_t *)operation->destination; int result = sourceValue + destinationValue; int halfResult = (sourceValue&0xfff) + (destinationValue&0xfff); bit3_result_ = bit5_result_ = (uint8_t)(result >> 8); carry_flag_ = (result >> 16) & Flag::Carry; half_carry_flag_ = (halfResult >> 8) & Flag::HalfCarry; subtract_flag_ = 0; *(uint16_t *)operation->destination = (uint16_t)result; } break; case MicroOp::ADC16: { uint16_t sourceValue = *(uint16_t *)operation->source; uint16_t destinationValue = *(uint16_t *)operation->destination; int result = sourceValue + destinationValue + carry_flag_; int halfResult = (sourceValue&0xfff) + (destinationValue&0xfff) + carry_flag_; int overflow = (result ^ destinationValue) & ~(destinationValue ^ sourceValue); bit5_result_ = bit3_result_ = sign_result_ = (uint8_t)(result >> 8); zero_result_ = (uint8_t)(result | sign_result_); subtract_flag_ = 0; carry_flag_ = result >> 16; half_carry_flag_ = (halfResult >> 8) & Flag::HalfCarry; parity_overflow_flag_ = (overflow & 0x8000) >> 13; *(uint16_t *)operation->destination = (uint16_t)result; } break; case MicroOp::SBC16: { uint16_t sourceValue = *(uint16_t *)operation->source; uint16_t destinationValue = *(uint16_t *)operation->destination; int result = destinationValue - sourceValue - carry_flag_; int halfResult = (destinationValue&0xfff) - (sourceValue&0xfff) - carry_flag_; // subtraction, so parity rules are: // signs of operands were different, // sign of result is different int overflow = (result ^ destinationValue) & (sourceValue ^ destinationValue); bit5_result_ = bit3_result_ = sign_result_ = (uint8_t)(result >> 8); zero_result_ = (uint8_t)(result | sign_result_); subtract_flag_ = Flag::Subtract; carry_flag_ = (result >> 16) & Flag::Carry; half_carry_flag_ = (halfResult >> 8) & Flag::HalfCarry; parity_overflow_flag_ = (overflow & 0x8000) >> 13; *(uint16_t *)operation->destination = (uint16_t)result; } break; #pragma mark - Conditionals case MicroOp::TestNZ: if(!zero_result_) { move_to_next_program(); checkSchedule(); } break; case MicroOp::TestZ: if(zero_result_) { move_to_next_program(); checkSchedule(); } break; case MicroOp::TestNC: if(carry_flag_) { move_to_next_program(); checkSchedule(); } break; case MicroOp::TestC: if(!carry_flag_) { move_to_next_program(); checkSchedule(); } break; case MicroOp::TestPO: if(parity_overflow_flag_) { move_to_next_program(); checkSchedule(); } break; case MicroOp::TestPE: if(!parity_overflow_flag_) { move_to_next_program(); checkSchedule(); } break; case MicroOp::TestP: if(sign_result_ & 0x80) { move_to_next_program(); checkSchedule(); } break; case MicroOp::TestM: if(!(sign_result_ & 0x80)) { move_to_next_program(); checkSchedule(); } break; #pragma mark - Exchange #define swap(a, b) temp = a.full; a.full = b.full; b.full = temp; case MicroOp::ExDEHL: { uint16_t temp; swap(de_, hl_); } break; case MicroOp::ExAFAFDash: { uint8_t a = a_; uint8_t f = get_flags(); set_flags(afDash_.bytes.low); a_ = afDash_.bytes.high; afDash_.bytes.high = a; afDash_.bytes.low = f; } break; case MicroOp::EXX: { uint16_t temp; swap(de_, deDash_); swap(bc_, bcDash_); swap(hl_, hlDash_); } break; #undef swap #pragma mark - Repetition #define REPEAT(test) \ if(test) { \ pc_.full -= 2; \ } else { \ move_to_next_program(); \ checkSchedule(); \ } #define LDxR_STEP(incr) \ bc_.full--; \ de_.full += (operation->type == incr) ? 1 : -1; \ hl_.full += (operation->type == incr) ? 1 : -1; \ bit3_result_ = bit5_result_ = a_ + temp8_; \ subtract_flag_ = 0; \ half_carry_flag_ = 0; \ parity_overflow_flag_ = bc_.full ? Flag::Parity : 0; case MicroOp::LDDR: case MicroOp::LDIR: { LDxR_STEP(MicroOp::LDIR); REPEAT(bc_.full); } break; case MicroOp::LDD: case MicroOp::LDI: { LDxR_STEP(MicroOp::LDI); } break; #undef LDxR_STEP #define CPxR_STEP(incr) \ hl_.full += (operation->type == incr) ? 1 : -1; \ bc_.full--; \ \ uint8_t result = a_ - temp8_; \ uint8_t halfResult = (a_&0xf) - (temp8_&0xf); \ \ parity_overflow_flag_ = bc_.full ? Flag::Parity : 0; \ half_carry_flag_ = halfResult & Flag::HalfCarry; \ subtract_flag_ = Flag::Subtract; \ bit5_result_ = bit3_result_ = (uint8_t)((result&0x8) | ((result&0x2) << 4)); \ sign_result_ = zero_result_ = result; case MicroOp::CPDR: case MicroOp::CPIR: { CPxR_STEP(MicroOp::CPIR); REPEAT(bc_.full); } break; case MicroOp::CPD: case MicroOp::CPI: { CPxR_STEP(MicroOp::CPI); } break; #undef CPxR_STEP #define INxR_STEP(incr) \ bc_.bytes.high--; \ hl_.full += (operation->type == incr) ? 1 : -1; \ \ sign_result_ = zero_result_ = bit3_result_ = bit5_result_ = bc_.bytes.high; \ subtract_flag_ = (temp8_ >> 6) & Flag::Subtract; \ \ int next_bc = bc_.bytes.low + ((operation->type == incr) ? 1 : -1); \ int summation = temp8_ + (next_bc&0xff); \ \ if(summation > 0xff) { \ carry_flag_ = Flag::Carry; \ half_carry_flag_ = Flag::HalfCarry; \ } else { \ carry_flag_ = 0; \ half_carry_flag_ = 0; \ } \ \ summation = (summation&7) ^ bc_.bytes.high; \ set_parity(summation); case MicroOp::INDR: case MicroOp::INIR: { INxR_STEP(MicroOp::INIR); REPEAT(bc_.bytes.high); } break; case MicroOp::IND: case MicroOp::INI: { INxR_STEP(MicroOp::INI); } break; #undef INxR_STEP #define OUTxR_STEP(incr) \ bc_.bytes.high--; \ hl_.full += (operation->type == incr) ? 1 : -1; \ \ sign_result_ = zero_result_ = bit5_result_ = bit3_result_ = bc_.bytes.high; \ subtract_flag_ = (temp8_ >> 6) & Flag::Subtract; \ \ int summation = temp8_ + hl_.bytes.low; \ if(summation > 0xff) { \ carry_flag_ = Flag::Carry; \ half_carry_flag_ = Flag::HalfCarry; \ } else { \ carry_flag_ = half_carry_flag_ = 0; \ } \ \ summation = (summation&7) ^ bc_.bytes.high; \ set_parity(summation); case MicroOp::OUTDR: case MicroOp::OUTIR: { OUTxR_STEP(MicroOp::OUTIR); REPEAT(bc_.bytes.high); } break; case MicroOp::OUTD: case MicroOp::OUTI: { OUTxR_STEP(MicroOp::OUTI); } break; #undef OUTxR_STEP #pragma mark - Bit Manipulation case MicroOp::BIT: { uint8_t result = *(uint8_t *)operation->source & (1 << ((operation_ >> 3)&7)); sign_result_ = zero_result_ = result; bit3_result_ = bit5_result_ = *(uint8_t *)operation->source; // This is a divergence between FUSE and The Undocumented Z80 Documented. half_carry_flag_ = Flag::HalfCarry; subtract_flag_ = 0; parity_overflow_flag_ = result ? 0 : Flag::Parity; } break; case MicroOp::RES: *(uint8_t *)operation->source &= ~(1 << ((operation_ >> 3)&7)); break; case MicroOp::SET: *(uint8_t *)operation->source |= (1 << ((operation_ >> 3)&7)); break; #pragma mark - Rotation and shifting #define set_rotate_flags() \ bit3_result_ = bit5_result_ = a_; \ carry_flag_ = new_carry; \ subtract_flag_ = half_carry_flag_ = 0; case MicroOp::RLA: { uint8_t new_carry = a_ >> 7; a_ = (uint8_t)((a_ << 1) | carry_flag_); set_rotate_flags(); } break; case MicroOp::RRA: { uint8_t new_carry = a_ & 1; a_ = (uint8_t)((a_ >> 1) | (carry_flag_ << 7)); set_rotate_flags(); } break; case MicroOp::RLCA: { uint8_t new_carry = a_ >> 7; a_ = (uint8_t)((a_ << 1) | new_carry); set_rotate_flags(); } break; case MicroOp::RRCA: { uint8_t new_carry = a_ & 1; a_ = (uint8_t)((a_ >> 1) | (new_carry << 7)); set_rotate_flags(); } break; #undef set_rotate_flags #define set_shift_flags() \ sign_result_ = zero_result_ = bit5_result_ = bit3_result_ = *(uint8_t *)operation->source; \ set_parity(sign_result_); \ half_carry_flag_ = 0; \ subtract_flag_ = 0; case MicroOp::RLC: carry_flag_ = *(uint8_t *)operation->source >> 7; *(uint8_t *)operation->source = (uint8_t)((*(uint8_t *)operation->source << 1) | carry_flag_); set_shift_flags(); break; case MicroOp::RRC: carry_flag_ = *(uint8_t *)operation->source & 1; *(uint8_t *)operation->source = (uint8_t)((*(uint8_t *)operation->source >> 1) | (carry_flag_ << 7)); set_shift_flags(); break; case MicroOp::RL: { uint8_t next_carry = *(uint8_t *)operation->source >> 7; *(uint8_t *)operation->source = (uint8_t)((*(uint8_t *)operation->source << 1) | carry_flag_); carry_flag_ = next_carry; set_shift_flags(); } break; case MicroOp::RR: { uint8_t next_carry = *(uint8_t *)operation->source & 1; *(uint8_t *)operation->source = (uint8_t)((*(uint8_t *)operation->source >> 1) | (carry_flag_ << 7)); carry_flag_ = next_carry; set_shift_flags(); } break; case MicroOp::SLA: carry_flag_ = *(uint8_t *)operation->source >> 7; *(uint8_t *)operation->source = (uint8_t)(*(uint8_t *)operation->source << 1); set_shift_flags(); break; case MicroOp::SRA: carry_flag_ = *(uint8_t *)operation->source & 1; *(uint8_t *)operation->source = (uint8_t)((*(uint8_t *)operation->source >> 1) | (*(uint8_t *)operation->source & 0x80)); set_shift_flags(); break; case MicroOp::SLL: carry_flag_ = *(uint8_t *)operation->source >> 7; *(uint8_t *)operation->source = (uint8_t)(*(uint8_t *)operation->source << 1) | 1; set_shift_flags(); break; case MicroOp::SRL: carry_flag_ = *(uint8_t *)operation->source & 1; *(uint8_t *)operation->source = (uint8_t)((*(uint8_t *)operation->source >> 1)); set_shift_flags(); break; #undef set_shift_flags #define set_decimal_rotate_flags() \ subtract_flag_ = 0; \ half_carry_flag_ = 0; \ set_parity(a_); \ bit3_result_ = bit5_result_ = zero_result_ = sign_result_ = a_; case MicroOp::RRD: { uint8_t low_nibble = a_ & 0xf; a_ = (a_ & 0xf0) | (temp8_ & 0xf); temp8_ = (temp8_ >> 4) | (low_nibble << 4); set_decimal_rotate_flags(); } break; case MicroOp::RLD: { uint8_t low_nibble = a_ & 0xf; a_ = (a_ & 0xf0) | (temp8_ >> 4); temp8_ = (temp8_ << 4) | low_nibble; set_decimal_rotate_flags(); } break; #undef set_decimal_rotate_flags #pragma mark - Interrupt state case MicroOp::EI: iff1_ = iff2_ = true; break; case MicroOp::DI: iff1_ = iff2_ = false; break; case MicroOp::IM: switch(operation_ & 0x18) { case 0x00: interrupt_mode_ = 0; break; case 0x08: interrupt_mode_ = 0; break; // IM 0/1 case 0x10: interrupt_mode_ = 1; break; case 0x18: interrupt_mode_ = 2; break; } break; #pragma mark - Input case MicroOp::SetInFlags: subtract_flag_ = half_carry_flag_ = 0; sign_result_ = zero_result_ = bit3_result_ = bit5_result_ = *(uint8_t *)operation->source; set_parity(sign_result_); break; case MicroOp::SetAFlags: subtract_flag_ = half_carry_flag_ = 0; parity_overflow_flag_ = iff2_ ? Flag::Parity : 0; sign_result_ = zero_result_ = bit3_result_ = bit5_result_ = a_; break; case MicroOp::SetZero: temp8_ = 0; break; #pragma mark - Return case MicroOp::RETN: iff1_ = iff2_; break; #pragma mark - Internal bookkeeping case MicroOp::SetInstructionPage: current_instruction_page_ = (InstructionPage *)operation->source; schedule_program(current_instruction_page_->fetch_decode_execute); break; case MicroOp::CalculateIndexAddress: temp16_.full = *(uint16_t *)operation->source + (int8_t)temp8_; break; case MicroOp::None: { uint8_t page = 0x00; if(current_instruction_page_ == &ed_page_) page = 0xed; if(current_instruction_page_ == &fd_page_) page = 0xfd; printf("Unknown Z80 operation %02x %02x!!!\n", page, operation_); } return; case MicroOp::IndexedPlaceHolder: printf("Hit placeholder!!!\n"); return; } #undef set_parity } } /*! Called to announce the end of a run_for_cycles period, allowing deferred work to take place. Users of the Z80 template may override this. */ void flush() {} int perform_machine_cycle(const MachineCycle *cycle) { return 0; } /*! Gets the flags register. @see set_flags @returns The current value of the flags register. */ uint8_t get_flags() { uint8_t result = (sign_result_ & Flag::Sign) | (zero_result_ ? 0 : Flag::Zero) | (bit5_result_ & Flag::Bit5) | half_carry_flag_ | (bit3_result_ & Flag::Bit3) | parity_overflow_flag_ | subtract_flag_ | carry_flag_; return result; } /*! Sets the flags register. @see set_flags @param flags The new value of the flags register. */ void set_flags(uint8_t flags) { sign_result_ = flags; zero_result_ = (flags & Flag::Zero) ^ Flag::Zero; bit5_result_ = flags; half_carry_flag_ = flags & Flag::HalfCarry; bit3_result_ = flags; parity_overflow_flag_ = flags & Flag::Parity; subtract_flag_ = flags & Flag::Subtract; carry_flag_ = flags & Flag::Carry; } /*! Gets the value of a register. @see set_value_of_register @param r The register to set. @returns The value of the register. 8-bit registers will be returned as unsigned. */ uint16_t get_value_of_register(Register r) { switch (r) { case Register::ProgramCounter: return pc_.full; case Register::StackPointer: return sp_.full; case Register::A: return a_; case Register::Flags: return get_flags(); case Register::AF: return (uint16_t)((a_ << 8) | get_flags()); case Register::B: return bc_.bytes.high; case Register::C: return bc_.bytes.low; case Register::BC: return bc_.full; case Register::D: return de_.bytes.high; case Register::E: return de_.bytes.low; case Register::DE: return de_.full; case Register::H: return hl_.bytes.high; case Register::L: return hl_.bytes.low; case Register::HL: return hl_.full; case Register::ADash: return afDash_.bytes.high; case Register::FlagsDash: return afDash_.bytes.low; case Register::AFDash: return afDash_.full; case Register::BDash: return bcDash_.bytes.high; case Register::CDash: return bcDash_.bytes.low; case Register::BCDash: return bcDash_.full; case Register::DDash: return deDash_.bytes.high; case Register::EDash: return deDash_.bytes.low; case Register::DEDash: return deDash_.full; case Register::HDash: return hlDash_.bytes.high; case Register::LDash: return hlDash_.bytes.low; case Register::HLDash: return hlDash_.full; case Register::IXh: return ix_.bytes.high; case Register::IXl: return ix_.bytes.low; case Register::IX: return ix_.full; case Register::IYh: return iy_.bytes.high; case Register::IYl: return iy_.bytes.low; case Register::IY: return iy_.full; case Register::R: return r_; case Register::I: return i_; case Register::IFF1: return iff1_ ? 1 : 0; case Register::IFF2: return iff2_ ? 1 : 0; case Register::IM: return interrupt_mode_; default: return 0; } } /*! Sets the value of a register. @see get_value_of_register @param r The register to set. @param value The value to set. If the register is only 8 bit, the value will be truncated. */ void set_value_of_register(Register r, uint16_t value) { switch (r) { case Register::ProgramCounter: pc_.full = value; break; case Register::StackPointer: sp_.full = value; break; case Register::A: a_ = (uint8_t)value; break; case Register::AF: a_ = (uint8_t)(value >> 8); // deliberate fallthrough... case Register::Flags: set_flags((uint8_t)value); break; case Register::B: bc_.bytes.high = (uint8_t)value; break; case Register::C: bc_.bytes.low = (uint8_t)value; break; case Register::BC: bc_.full = value; break; case Register::D: de_.bytes.high = (uint8_t)value; break; case Register::E: de_.bytes.low = (uint8_t)value; break; case Register::DE: de_.full = value; break; case Register::H: hl_.bytes.high = (uint8_t)value; break; case Register::L: hl_.bytes.low = (uint8_t)value; break; case Register::HL: hl_.full = value; break; case Register::ADash: afDash_.bytes.high = (uint8_t)value; break; case Register::FlagsDash: afDash_.bytes.low = (uint8_t)value; break; case Register::AFDash: afDash_.full = value; break; case Register::BDash: bcDash_.bytes.high = (uint8_t)value; break; case Register::CDash: bcDash_.bytes.low = (uint8_t)value; break; case Register::BCDash: bcDash_.full = value; break; case Register::DDash: deDash_.bytes.high = (uint8_t)value; break; case Register::EDash: deDash_.bytes.low = (uint8_t)value; break; case Register::DEDash: deDash_.full = value; break; case Register::HDash: hlDash_.bytes.high = (uint8_t)value; break; case Register::LDash: hlDash_.bytes.low = (uint8_t)value; break; case Register::HLDash: hlDash_.full = value; break; case Register::IXh: ix_.bytes.high = (uint8_t)value; break; case Register::IXl: ix_.bytes.low = (uint8_t)value; break; case Register::IX: ix_.full = value; break; case Register::IYh: iy_.bytes.high = (uint8_t)value; break; case Register::IYl: iy_.bytes.low = (uint8_t)value; break; case Register::IY: iy_.full = value; break; case Register::R: r_ = (uint8_t)value; break; case Register::I: i_ = (uint8_t)value; break; case Register::IFF1: iff1_ = !!value; break; case Register::IFF2: iff2_ = !!value; break; case Register::IM: interrupt_mode_ = value % 2; break; default: break; } } }; } } #endif /* Z80_hpp */