Jak to kodowanie gier kiedyś wyglądało

Tony Porter (Gauntlet – Tony had the ‘simple task’ of converting it for the ZX Spectrum):
One thing I will never forget. As we worked though the arcade machine’s code dump I spotted a hex dump of something that looked familiar… It was Z80 code. I typed it back in, disassembled it and then worked out what it was for. The coin-op machine actually had a Z80 processor in it. The code’s purpose became clear. While we were trying to write the whole thing – logic, graphics, sound, the whole ball game – on a Z80 processor, the arcade machine used the same processor solely to read the joysticks, buttons and
coin slots!
ZA The Story of US Gold Chris Wilkins & Roger M. Kean