#include #include #include "cpu.h" enum addressing_mode { AM_NONE, AM_ACC, AM_IMM, AM_REL, AM_ZP, AM_ZP_X, AM_ZP_Y, AM_ABS, AM_ABS_X, AM_ABS_Y, AM_IND, AM_IND_X, AM_IND_Y, }; /* index of below array is the code of the instruction */ struct opcode { const char name[4]; /* I know 16bit seems wasteful, but some ops use 16bit memory as arg */ void (*instr)(uint16_t arg); uint8_t bytes; uint8_t cycles; bool memread; bool memwrite; enum addressing_mode mode; }; struct opcode opcodes[0x100] = { /* official opcodes */ [0x69] = { "ADC", ADC, 2, 2, false, false, AM_IMM }, [0x65] = { "ADC", ADC, 2, 3, true, false, AM_ZP }, [0x75] = { "ADC", ADC, 2, 4, true, false, AM_ZP_X }, [0x6D] = { "ADC", ADC, 3, 4, true, false, AM_ABS }, [0x7D] = { "ADC", ADC, 3, 4, true, false, AM_ABS_X }, [0x79] = { "ADC", ADC, 3, 4, true, false, AM_ABS_Y }, [0x61] = { "ADC", ADC, 2, 6, true, false, AM_IND_X }, [0x71] = { "ADC", ADC, 2, 5, true, false, AM_IND_Y }, [0x29] = { "AND", AND, 2, 2, false, false, AM_IMM }, [0x25] = { "AND", AND, 2, 3, true, false, AM_ZP }, [0x35] = { "AND", AND, 2, 4, true, false, AM_ZP_X }, [0x2D] = { "AND", AND, 3, 4, true, false, AM_ABS }, [0x3D] = { "AND", AND, 3, 4, true, false, AM_ABS_X }, [0x39] = { "AND", AND, 3, 4, true, false, AM_ABS_Y }, [0x21] = { "AND", AND, 2, 6, true, false, AM_IND_X }, [0x31] = { "AND", AND, 2, 5, true, false, AM_IND_Y }, [0x0A] = { "ASL", ASL_acc, 1, 2, false, false, AM_ACC }, [0x06] = { "ASL", ASL, 2, 5, false, true, AM_ZP }, [0x16] = { "ASL", ASL, 2, 6, false, true, AM_ZP_X }, [0x0E] = { "ASL", ASL, 3, 6, false, true, AM_ABS }, [0x1E] = { "ASL", ASL, 3, 7, false, true, AM_ABS_X }, [0x90] = { "BCC", BCC, 2, 2, false, false, AM_REL }, [0xB0] = { "BCS", BCS, 2, 2, false, false, AM_REL }, [0xF0] = { "BEQ", BEQ, 2, 2, false, false, AM_REL }, [0x24] = { "BIT", BIT, 2, 3, true, false, AM_ZP }, [0x2C] = { "BIT", BIT, 3, 4, true, false, AM_ABS }, [0x30] = { "BMI", BMI, 2, 2, false, false, AM_REL }, [0xD0] = { "BNE", BNE, 2, 2, false, false, AM_REL }, [0x10] = { "BPL", BPL, 2, 2, false, false, AM_REL }, [0x00] = { "BRK", BRK, 1, 7, false, false, AM_NONE }, [0x50] = { "BVC", BVC, 2, 2, false, false, AM_REL }, [0x70] = { "BVS", BVS, 2, 2, false, false, AM_REL }, [0x18] = { "CLC", CLC, 1, 2, false, false, AM_NONE }, [0xD8] = { "CLD", CLD, 1, 2, false, false, AM_NONE }, [0x58] = { "CLI", CLI, 1, 2, false, false, AM_NONE }, [0xB8] = { "CLV", CLV, 1, 2, false, false, AM_NONE }, [0xC9] = { "CMP", CMP, 2, 2, false, false, AM_IMM }, [0xC5] = { "CMP", CMP, 2, 3, true, false, AM_ZP }, [0xD5] = { "CMP", CMP, 2, 4, true, false, AM_ZP_X }, [0xCD] = { "CMP", CMP, 3, 4, true, false, AM_ABS }, [0xDD] = { "CMP", CMP, 3, 4, true, false, AM_ABS_X }, [0xD9] = { "CMP", CMP, 3, 4, true, false, AM_ABS_Y }, [0xC1] = { "CMP", CMP, 2, 6, true, false, AM_IND_X }, [0xD1] = { "CMP", CMP, 2, 5, true, false, AM_IND_Y }, [0xE0] = { "CPX", CPX, 2, 2, false, false, AM_IMM }, [0xE4] = { "CPX", CPX, 2, 3, true, false, AM_ZP }, [0xEC] = { "CPX", CPX, 3, 4, true, false, AM_ABS }, [0xC0] = { "CPY", CPY, 2, 2, false, false, AM_IMM }, [0xC4] = { "CPY", CPY, 2, 3, true, false, AM_ZP }, [0xCC] = { "CPY", CPY, 3, 4, true, false, AM_ABS }, [0xC6] = { "DEC", DEC, 2, 5, false, true, AM_ZP }, [0xD6] = { "DEC", DEC, 2, 6, false, true, AM_ZP_X }, [0xCE] = { "DEC", DEC, 3, 6, false, true, AM_ABS }, [0xDE] = { "DEC", DEC, 3, 7, false, true, AM_ABS_X }, [0xCA] = { "DEX", DEX, 1, 2, false, false, AM_NONE }, [0x88] = { "DEY", DEY, 1, 2, false, false, AM_NONE }, [0x49] = { "EOR", EOR, 2, 2, false, false, AM_IMM }, [0x45] = { "EOR", EOR, 2, 3, true, false, AM_ZP }, [0x55] = { "EOR", EOR, 2, 4, true, false, AM_ZP_X }, [0x4D] = { "EOR", EOR, 3, 4, true, false, AM_ABS }, [0x5D] = { "EOR", EOR, 3, 4, true, false, AM_ABS_X }, [0x59] = { "EOR", EOR, 3, 4, true, false, AM_ABS_Y }, [0x41] = { "EOR", EOR, 2, 6, true, false, AM_IND_X }, [0x51] = { "EOR", EOR, 2, 5, true, false, AM_IND_Y }, [0xE6] = { "INC", INC, 2, 5, false, true, AM_ZP }, [0xF6] = { "INC", INC, 2, 6, false, true, AM_ZP_X }, [0xEE] = { "INC", INC, 3, 6, false, true, AM_ABS }, [0xFE] = { "INC", INC, 3, 7, false, true, AM_ABS_X }, [0xE8] = { "INX", INX, 1, 2, false, false, AM_NONE }, [0xC8] = { "INY", INY, 1, 2, false, false, AM_NONE }, [0x4C] = { "JMP", JMP, 3, 3, false, false, AM_ABS }, [0x6C] = { "JMP", JMP, 3, 5, false, false, AM_IND }, [0x20] = { "JSR", JSR, 3, 6, false, false, AM_ABS }, [0xA9] = { "LDA", LDA, 2, 2, false, false, AM_IMM }, [0xA5] = { "LDA", LDA, 2, 3, true, false, AM_ZP }, [0xB5] = { "LDA", LDA, 2, 4, true, false, AM_ZP_X }, [0xAD] = { "LDA", LDA, 3, 4, true, false, AM_ABS }, [0xBD] = { "LDA", LDA, 3, 4, true, false, AM_ABS_X }, [0xB9] = { "LDA", LDA, 3, 4, true, false, AM_ABS_Y }, [0xA1] = { "LDA", LDA, 2, 6, true, false, AM_IND_X }, [0xB1] = { "LDA", LDA, 2, 5, true, false, AM_IND_Y }, [0xA2] = { "LDX", LDX, 2, 2, false, false, AM_IMM }, [0xA6] = { "LDX", LDX, 2, 3, true, false, AM_ZP }, [0xB6] = { "LDX", LDX, 2, 4, true, false, AM_ZP_Y }, [0xAE] = { "LDX", LDX, 3, 4, true, false, AM_ABS }, [0xBE] = { "LDX", LDX, 3, 4, true, false, AM_ABS_Y }, [0xA0] = { "LDY", LDY, 2, 2, false, false, AM_IMM }, [0xA4] = { "LDY", LDY, 2, 3, true, false, AM_ZP }, [0xB4] = { "LDY", LDY, 2, 4, true, false, AM_ZP_X }, [0xAC] = { "LDY", LDY, 3, 4, true, false, AM_ABS }, [0xBC] = { "LDY", LDY, 3, 4, true, false, AM_ABS_X }, [0x4A] = { "LSR", LSR_acc, 1, 2, false, false, AM_ACC }, [0x46] = { "LSR", LSR, 2, 5, false, true, AM_ZP }, [0x56] = { "LSR", LSR, 2, 6, false, true, AM_ZP_X }, [0x4E] = { "LSR", LSR, 3, 6, false, true, AM_ABS }, [0x5E] = { "LSR", LSR, 3, 7, false, true, AM_ABS_X }, [0xEA] = { "NOP", NOP, 1, 2, false, false, AM_NONE }, [0x09] = { "ORA", ORA, 2, 2, false, false, AM_IMM }, [0x05] = { "ORA", ORA, 2, 3, true, false, AM_ZP }, [0x15] = { "ORA", ORA, 2, 4, true, false, AM_ZP_X }, [0x0D] = { "ORA", ORA, 3, 4, true, false, AM_ABS }, [0x1D] = { "ORA", ORA, 3, 4, true, false, AM_ABS_X }, [0x19] = { "ORA", ORA, 3, 4, true, false, AM_ABS_Y }, [0x01] = { "ORA", ORA, 2, 6, true, false, AM_IND_X }, [0x11] = { "ORA", ORA, 2, 5, true, false, AM_IND_Y }, [0x48] = { "PHA", PHA, 1, 3, false, false, AM_NONE }, [0x08] = { "PHP", PHP, 1, 3, false, false, AM_NONE }, [0x68] = { "PLA", PLA, 1, 4, false, false, AM_NONE }, [0x28] = { "PLP", PLP, 1, 4, false, false, AM_NONE }, [0x2A] = { "ROL", ROL_acc, 1, 2, false, false, AM_ACC }, [0x26] = { "ROL", ROL, 2, 5, false, true, AM_ZP }, [0x36] = { "ROL", ROL, 2, 6, false, true, AM_ZP_X }, [0x2E] = { "ROL", ROL, 3, 6, false, true, AM_ABS }, [0x3E] = { "ROL", ROL, 3, 7, false, true, AM_ABS_X }, [0x6A] = { "ROR", ROR_acc, 1, 2, false, false, AM_ACC }, [0x66] = { "ROR", ROR, 2, 5, false, true, AM_ZP }, [0x76] = { "ROR", ROR, 2, 6, false, true, AM_ZP_X }, [0x6E] = { "ROR", ROR, 3, 6, false, true, AM_ABS }, [0x7E] = { "ROR", ROR, 3, 7, false, true, AM_ABS_X }, [0x40] = { "RTI", RTI, 1, 6, false, false, AM_NONE }, [0x60] = { "RTS", RTS, 1, 6, false, false, AM_NONE }, [0xE9] = { "SBC", SBC, 2, 2, false, false, AM_IMM }, [0xE5] = { "SBC", SBC, 2, 3, true, false, AM_ZP }, [0xF5] = { "SBC", SBC, 2, 4, true, false, AM_ZP_X }, [0xED] = { "SBC", SBC, 3, 4, true, false, AM_ABS }, [0xFD] = { "SBC", SBC, 3, 4, true, false, AM_ABS_X }, [0xF9] = { "SBC", SBC, 3, 4, true, false, AM_ABS_Y }, [0xE1] = { "SBC", SBC, 2, 6, true, false, AM_IND_X }, [0xF1] = { "SBC", SBC, 2, 5, true, false, AM_IND_Y }, [0x38] = { "SEC", SEC, 1, 2, false, false, AM_NONE }, [0xF8] = { "SED", SED, 1, 2, false, false, AM_NONE }, [0x78] = { "SEI", SEI, 1, 2, false, false, AM_NONE }, [0x85] = { "STA", STA, 2, 3, false, true, AM_ZP }, [0x95] = { "STA", STA, 2, 4, false, true, AM_ZP_X }, [0x8D] = { "STA", STA, 3, 4, false, true, AM_ABS }, [0x9D] = { "STA", STA, 3, 5, false, true, AM_ABS_X }, [0x99] = { "STA", STA, 3, 5, false, true, AM_ABS_Y }, [0x81] = { "STA", STA, 2, 6, false, true, AM_IND_X }, [0x91] = { "STA", STA, 2, 6, false, true, AM_IND_Y }, [0x86] = { "STX", STX, 2, 3, false, true, AM_ZP }, [0x96] = { "STX", STX, 2, 4, false, true, AM_ZP_Y }, [0x8E] = { "STX", STX, 3, 4, false, true, AM_ABS }, [0x84] = { "STY", STY, 2, 3, false, true, AM_ZP }, [0x94] = { "STY", STY, 2, 4, false, true, AM_ZP_X }, [0x8C] = { "STY", STY, 3, 4, false, true, AM_ABS }, [0xAA] = { "TAX", TAX, 1, 2, false, false, AM_NONE }, [0xA8] = { "TAY", TAY, 1, 2, false, false, AM_NONE }, [0xBA] = { "TSX", TSX, 1, 2, false, false, AM_NONE }, [0x8A] = { "TXA", TXA, 1, 2, false, false, AM_NONE }, [0x9A] = { "TXS", TXS, 1, 2, false, false, AM_NONE }, [0x98] = { "TYA", TYA, 1, 2, false, false, AM_NONE }, };