* [https://zxe.io/software/Z80/ libZ80] Ultra accurate ANSI C implementation
* [[arnold]] uses [[InkZ80]], written in C++ (apart taken from the author-designed C simulation[http://www.inkland.org.uk/inkspector/index.htm InkSpector] ZX Spectrum emulator)
* [https://opencores.org/projects/a-z80 A-Z80] Ultra accurate Verilog implementation