Changes

*[https://pastraiser.com/cpu/Z80/Z80_opcodes.html Zilog Z80 instruction set]

*[http://www.z80.info/decoding.htm Decoding Z80 opcodes]

*[https://baltazarstudios.com/zilog-z80-undocumented-behavior/ Complete list of Z80 instructions and their bus responses and cycles dumped from real hardware]

*[https://floooh.github.io/2021/12/06/z80-instruction-timing.html Detailed look at Z80 instruction timings with the help of a Z80 netlist simulation]