what I have been searching for years is not theories or tutorials about PID, but a detailed explanation on how to tune a digital controller(instead of a continu

what I have been searching for years is not theories or tutorials about PID, but a detailed explanation on how to tune a digital controller(instead of a continuous one) in a easy-to-setup environment, whether it be simulation or a cheap hardware. I know examples can include inverted pendulum(IP), double IP, mountain cart, heater with thermometer feedback, line-follower, etc, but where can I easily play around with these examples?