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User:Brantmeierz/Opcode prefix

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A opcode prefix or prefix byte is a portion of an instruction that allows for a extended set of instructions to follow it by expanding an existing opcode with independent functions. Prefixed opcodes are those existing inside of the instruction subset created by the opcode prefix.

Opcode prefixes by architecture

x86

Z80

  • CB, DD, ED, FD[2]

References

  1. ^ "x86 Instruction Prefix Bytes". www.c-jump.com. Retrieved 31 May 2018.
  2. ^ Dinu, Cristian. "Decoding Z80 Opcodes". www.z80.info. Retrieved 31 May 2018.