comp.sys.sinclair FAQ

Zilog Z80A Technical Information

Zilog Z80A CPU:
Most Z80 opcodes are one byte long, not counting a possible byte or word operand. The four opcodes CB, DD, ED and FD change the meaning of the opcode following them. You may find it helpful to use this reference section in conjunction with the 'Z80 Datasheet', 'The Undocumented Z80 Documented' and 'Z80 CPU Users Manual', each of which are available from Sean Young's web site, and the Z80 CPU Official Support Page, maintained by Gaby Chaudry

There are 7 subsections available: CB Opcodes, ED Opcodes, DD and FD Opcodes, DAA, The R Register, Undocumented Flags and Interrupts.