diff --git a/lib/opcode80.asm b/lib/opcode80.asm
new file mode 100644
index 0000000..28412a9
--- /dev/null
+++ b/lib/opcode80.asm
@@ -0,0 +1,122 @@
+; BYTE      name length
+; n BYTES   name
+; BYTE      opcode template (variable parts zero)
+;
+; BYTE      operand 1
+; BYTE      operand 2
+
+; operand types:
+; 0x00      none
+; 0x1n      reg8, opcode |= (reg8 << n)
+; 0x2n      reg16, opcode |= (reg8 << n)
+; 0x3n      3-bit number, opcode |= (num << n)
+; 0x80      imm8, encoded as extra byte
+; 0x81      imm16, encoded as extra word
+
+reg8:
+  db "B",0,"C",0,"D",0,"E",0,"H",0,"L",0,"M",0
+
+reg16:
+  db "BC", "DE", "HL", "SP"
+
+opcodes:
+; Data movement
+  db 3, "MOV",  0b01000000, 0x13, 0x10
+  db 3, "MVI",  0b00000110, 0x13, 0x80
+  db 3, "LXI",  0b00000001, 0x24, 0x81
+  db 3, "LDA",  0b00111010, 0x81, 0x00
+  db 3, "STA",  0b00110010, 0x81, 0x00
+  db 4, "LHLD", 0b00101010, 0x81, 0x00
+  db 4, "SHLD", 0b00100010, 0x81, 0x00
+  db 4, "LDAX", 0b00001010, 0x24, 0x00
+  db 4, "STAX", 0b00000010, 0x24, 0x00
+  db 4, "XCHG", 0b11101011, 0x00, 0x00
+
+; Addition / Subtraction
+  db 3, "ADD",  0b10000000, 0x10, 0x00
+  db 3, "ADI",  0b11000110, 0x80, 0x00
+  db 3, "ADC",  0b10001000, 0x10, 0x00
+  db 3, "ACI",  0b11001110, 0x80, 0x00
+  db 3, "SUB",  0b10010000, 0x10, 0x00
+  db 3, "SUI",  0b11010110, 0x80, 0x00
+  db 3, "SBB",  0b10011000, 0x10, 0x00
+  db 3, "SBI",  0b11011110, 0x80, 0x00
+  db 3, "INR",  0b00000100, 0x13, 0x00
+  db 3, "DCR",  0b00000101, 0x13, 0x00
+  db 3, "INX",  0b00000011, 0x24, 0x00
+  db 3, "DCX",  0b00001011, 0x24, 0x00
+  db 3, "DAD",  0b00001001, 0x24, 0x00
+
+; BCD
+  db 3, "DAA",  0b00100111, 0x00, 0x00
+
+; Bitwise operations
+  db 3, "ANA",  0b10100000, 0x10, 0x00
+  db 3, "ANI",  0b11100110, 0x80, 0x00
+  db 3, "ORA",  0b10110000, 0x10, 0x00
+  db 3, "ORI",  0b11110110, 0x80, 0x00
+  db 3, "XRA",  0b10101000, 0x10, 0x00
+  db 3, "XRI",  0b11101110, 0x80, 0x00
+  db 3, "CMP",  0b10111000, 0x10, 0x00
+  db 3, "CPI",  0b11111110, 0x80, 0x00
+
+; Rotate
+  db 3, "RLC",  0b00000111, 0x00, 0x00
+  db 3, "RRC",  0b00001111, 0x00, 0x00
+  db 3, "RAL",  0b00010111, 0x00, 0x00
+  db 3, "RAR",  0b00011111, 0x00, 0x00
+
+; Complement
+  db 3, "CMA",  0b00101111, 0x00, 0x00
+  db 3, "CMC",  0b00111111, 0x00, 0x00
+  db 3, "STC",  0b00110111, 0x00, 0x00
+
+; Jump
+  db 3, "JMP",  0b11000011, 0x81, 0x00
+  db 3, "JNZ",  0b11000010, 0x81, 0x00
+  db 2, "JZ",   0b11001010, 0x81, 0x00
+  db 3, "JNC",  0b11010010, 0x81, 0x00
+  db 2, "JC",   0b11011010, 0x81, 0x00
+  db 3, "JPO",  0b11100010, 0x81, 0x00
+  db 3, "JPE",  0b11101010, 0x81, 0x00
+  db 2, "JP",   0b11110010, 0x81, 0x00
+  db 2, "JM",   0b11111010, 0x81, 0x00
+
+; Call
+  db 4, "CALL", 0b11001101, 0x81, 0x00
+  db 3, "CNZ",  0b11000100, 0x81, 0x00
+  db 2, "CZ",   0b11001100, 0x81, 0x00
+  db 3, "CNC",  0b11010100, 0x81, 0x00
+  db 2, "CC",   0b11011100, 0x81, 0x00
+  db 3, "CPO",  0b11100100, 0x81, 0x00
+  db 3, "CPE",  0b11101100, 0x81, 0x00
+  db 2, "CP",   0b11110100, 0x81, 0x00
+  db 2, "CM",   0b11111100, 0x81, 0x00
+
+; Return
+  db 3, "RET",  0b11001001, 0x00, 0x00
+  db 3, "RNZ",  0b11000000, 0x00, 0x00
+  db 2, "RZ",   0b11001000, 0x00, 0x00
+  db 3, "RNC",  0b11010000, 0x00, 0x00
+  db 2, "RC",   0b11011000, 0x00, 0x00
+  db 3, "RPO",  0b11100000, 0x00, 0x00
+  db 3, "RPE",  0b11101000, 0x00, 0x00
+  db 2, "RP",   0b11110000, 0x00, 0x00
+  db 2, "RM",   0b11111000, 0x00, 0x00
+
+  db 3, "RST",  0b11000111, 0x33, 0x00
+  db 4, "PCHL", 0b11101001, 0x00, 0x00
+  db 4, "PUSH", 0b11000101, 0x24, 0x00
+  db 3, "POP",  0b11000001, 0x24, 0x00
+  db 4, "XTHL", 0b11100011, 0x00, 0x00
+  db 4, "SPHL", 0b11111001, 0x00, 0x00
+
+  db 2, "IN",   0b11011011, 0x80, 0x00
+  db 3, "OUT",  0b11010011, 0x80, 0x00
+
+  db 2, "EI",   0b11111011, 0x00, 0x00
+  db 2, "DI",   0b11110011, 0x00, 0x00
+  db 3, "HLT",  0b01110110, 0x00, 0x00
+  db 3, "NOP",  0b00000000, 0x00, 0x00
+
+  db 0