diff --git a/src/app/emu/internal/opcodes.h b/src/app/emu/internal/opcodes.h
new file mode 100644
index 00000000..ab112903
--- /dev/null
+++ b/src/app/emu/internal/opcodes.h
@@ -0,0 +1,61 @@
+#pragma once
+
+#include <cstdint>
+#include <string>
+#include <unordered_map>
+
+const std::unordered_map<uint8_t, std::string> opcode_to_mnemonic = {
+    {0x00, "BRK"}, {0x01, "ORA"}, {0x02, "COP"}, {0x03, "ORA"}, {0x04, "TSB"},
+    {0x05, "ORA"}, {0x06, "ASL"}, {0x07, "ORA"}, {0x08, "PHP"}, {0x09, "ORA"},
+    {0x0A, "ASL"}, {0x0B, "PHD"}, {0x0C, "TSB"}, {0x0D, "ORA"}, {0x0E, "ASL"},
+    {0x0F, "ORA"}, {0x10, "BPL"}, {0x11, "ORA"}, {0x12, "ORA"}, {0x13, "ORA"},
+    {0x14, "TRB"}, {0x15, "ORA"}, {0x16, "ASL"}, {0x17, "ORA"}, {0x18, "CLC"},
+    {0x19, "ORA"}, {0x1A, "INC"}, {0x1B, "TCS"}, {0x1C, "TRB"}, {0x1D, "ORA"},
+    {0x1E, "ASL"}, {0x1F, "ORA"}, {0x20, "JSR"}, {0x21, "AND"}, {0x22, "JSL"},
+    {0x23, "AND"}, {0x24, "BIT"}, {0x25, "AND"}, {0x26, "ROL"}, {0x27, "AND"},
+    {0x28, "PLP"}, {0x29, "AND"}, {0x2A, "ROL"}, {0x2B, "PLD"}, {0x2C, "BIT"},
+    {0x2D, "AND"}, {0x2E, "ROL"}, {0x2F, "AND"}, {0x30, "BMI"}, {0x31, "AND"},
+    {0x32, "AND"}, {0x33, "AND"}, {0x34, "BIT"}, {0x35, "AND"}, {0x36, "ROL"},
+    {0x37, "AND"}, {0x38, "SEC"}, {0x39, "AND"}, {0x3A, "DEC"}, {0x3B, "TSC"},
+    {0x3C, "BIT"}, {0x3D, "AND"}, {0x3E, "ROL"}, {0x3F, "AND"}, {0x40, "RTI"},
+    {0x41, "EOR"}, {0x42, "WDM"}, {0x43, "EOR"}, {0x44, "MVP"}, {0x45, "EOR"},
+    {0x46, "LSR"}, {0x47, "EOR"}, {0x48, "PHA"}, {0x49, "EOR"}, {0x4A, "LSR"},
+    {0x4B, "PHK"}, {0x4C, "JMP"}, {0x4D, "EOR"}, {0x4E, "LSR"}, {0x4F, "EOR"},
+    {0x50, "BVC"}, {0x51, "EOR"}, {0x52, "EOR"}, {0x53, "EOR"}, {0x54, "MVN"},
+    {0x55, "EOR"}, {0x56, "LSR"}, {0x57, "EOR"}, {0x58, "CLI"}, {0x59, "EOR"},
+    {0x5A, "PHY"}, {0x5B, "TCD"}, {0x5C, "JMP"}, {0x5D, "EOR"}, {0x5E, "LSR"},
+    {0x5F, "EOR"}, {0x60, "RTS"}, {0x61, "ADC"}, {0x62, "PER"}, {0x63, "ADC"},
+    {0x64, "STZ"}, {0x65, "ADC"}, {0x66, "ROR"}, {0x67, "ADC"}, {0x68, "PLA"},
+    {0x69, "ADC"}, {0x6A, "ROR"}, {0x6B, "RTL"}, {0x6C, "JMP"}, {0x6D, "ADC"},
+    {0x6E, "ROR"}, {0x6F, "ADC"}, {0x70, "BVS"}, {0x71, "ADC"}, {0x72, "ADC"},
+    {0x73, "ADC"}, {0x74, "STZ"}, {0x75, "ADC"}, {0x76, "ROR"}, {0x77, "ADC"},
+    {0x78, "SEI"}, {0x79, "ADC"}, {0x7A, "PLY"}, {0x7B, "TDC"}, {0x7C, "JMP"},
+    {0x7D, "ADC"}, {0x7E, "ROR"}, {0x7F, "ADC"}, {0x80, "BRA"}, {0x81, "STA"},
+    {0x82, "BRL"}, {0x83, "STA"}, {0x84, "STY"}, {0x85, "STA"}, {0x86, "STX"},
+    {0x87, "STA"}, {0x88, "DEY"}, {0x89, "BIT"}, {0x8A, "TXA"}, {0x8B, "PHB"},
+    {0x8C, "STY"}, {0x8D, "STA"}, {0x8E, "STX"}, {0x8F, "STA"}, {0x90, "BCC"},
+    {0x91, "STA"}, {0x92, "STA"}, {0x93, "STA"}, {0x94, "STY"}, {0x95, "STA"},
+    {0x96, "STX"}, {0x97, "STA"}, {0x98, "TYA"}, {0x99, "STA"}, {0x9A, "TXS"},
+    {0x9B, "TXY"}, {0x9C, "STZ"}, {0x9D, "STA"}, {0x9E, "STZ"}, {0x9F, "STA"},
+    {0xA0, "LDY"}, {0xA1, "LDA"}, {0xA2, "LDX"}, {0xA3, "LDA"}, {0xA4, "LDY"},
+    {0xA5, "LDA"}, {0xA6, "LDX"}, {0xA7, "LDA"}, {0xA8, "TAY"}, {0xA9, "LDA"},
+    {0xAA, "TAX"}, {0xAB, "PLB"}, {0xAC, "LDY"}, {0xAD, "LDA"}, {0xAE, "LDX"},
+    {0xAF, "LDA"}, {0xB0, "BCS"}, {0xB1, "LDA"}, {0xB2, "LDA"}, {0xB3, "LDA"},
+    {0xB4, "LDY"}, {0xB5, "LDA"}, {0xB6, "LDX"}, {0xB7, "LDA"}, {0xB8, "CLV"},
+    {0xB9, "LDA"}, {0xBA, "TSX"}, {0xBB, "TYX"}, {0xBC, "LDY"}, {0xBD, "LDA"},
+    {0xBE, "LDX"}, {0xBF, "LDA"}, {0xC0, "CPY"}, {0xC1, "CMP"}, {0xC2, "REP"},
+    {0xC3, "CMP"}, {0xC4, "CPY"}, {0xC5, "CMP"}, {0xC6, "DEC"}, {0xC7, "CMP"},
+    {0xC8, "INY"}, {0xC9, "CMP"}, {0xCA, "DEX"}, {0xCB, "WAI"}, {0xCC, "CPY"},
+    {0xCD, "CMP"}, {0xCE, "DEC"}, {0xCF, "CMP"}, {0xD0, "BNE"}, {0xD1, "CMP"},
+    {0xD2, "CMP"}, {0xD3, "CMP"}, {0xD4, "PEI"}, {0xD5, "CMP"}, {0xD6, "DEC"},
+    {0xD7, "CMP"}, {0xD8, "CLD"}, {0xD9, "CMP"}, {0xDA, "PHX"}, {0xDB, "STP"},
+    {0xDC, "JMP"}, {0xDD, "CMP"}, {0xDE, "DEC"}, {0xDF, "CMP"}, {0xE0, "CPX"},
+    {0xE1, "SBC"}, {0xE2, "SEP"}, {0xE3, "SBC"}, {0xE4, "CPX"}, {0xE5, "SBC"},
+    {0xE6, "INC"}, {0xE7, "SBC"}, {0xE8, "INX"}, {0xE9, "SBC"}, {0xEA, "NOP"},
+    {0xEB, "XBA"}, {0xEC, "CPX"}, {0xED, "SBC"}, {0xEE, "INC"}, {0xEF, "SBC"},
+    {0xF0, "BEQ"}, {0xF1, "SBC"}, {0xF2, "SBC"}, {0xF3, "SBC"}, {0xF4, "PEA"},
+    {0xF5, "SBC"}, {0xF6, "INC"}, {0xF7, "SBC"}, {0xF8, "SED"}, {0xF9, "SBC"},
+    {0xFA, "PLX"}, {0xFB, "XCE"}, {0xFC, "JSR"}, {0xFD, "SBC"}, {0xFE, "INC"},
+    {0xFF, "SBC"}
+
+};
\ No newline at end of file