If you have a terminal, fine. If you have a TRS-80, you could use that as well. It's just a prototype, but the potential is here to expand and modify into many useful things. It consists of the following circuit chips. It is erased electronically.
Timers are useful for one-shots or counting duration, or alarms for overtime, etc.
It might be a length of a tone, squirt of fuel or a douse of water, or a shot of air. How long it takes your little heater to heat the backyard pool up to comfy. Don't let the long technical name fool you. It's fairly simple. Basically, it provides the interface to a modem or to another computer.