In closing, here's an interesting question. If the round-robin switch had
numerous states, say a dozen or so, a single increment button might prove a
little frustrating to the user. For example, if they accidentally go past the
desired setting then they're forced to go all the way around again to
effectively "back up". To alleviate this we could add a decrement pushbutton
alongside our existing increment pushbutton. How would the code example
presented above need to be altered to respond to a two button configuration?
If at first this appears to be too daunting of a challenge, then break it into
two parts. Initially, consider how the preceding code would need to be altered
in order to change the operation of the fan speed increment button into a fan
speed decrement button. That is, instead of button pushes producing the
sequence offlow-med-high-off etc., implement the button to produce off-high-
med-low-off etc. Once this is completed, determine how to combine this new
implementation with the existing example code.
