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owl [soylentnews.org] writes:

The beer warms a bit as you pound the remote control. Again and again, temper fraying, you click the "channel up" key until the TV finally rewards your efforts. But it turns out channel 345 is playing Jeopardy so you again wave the remote in the general direction of the set and continue fiddling with the buttons.

Some remotes work astonishingly well, even when you bounce the beam off three walls before it impinges on the TV's IR detector. Others don't. One vendor told me reliability simply isn't important as users will subconsciously hit the button again and again till the channel changes.

When a single remote press causes the tube to jump two channels, we developers know lousy debounce code is at fault. The FM radio on my sailboat has a tuning button that advances too far when I hit it hard. The usual suspect: bounce.

When the contacts of any mechanical switch bang together they rebound a bit before settling, causing bounce. Debouncing, of course, is the process of removing the bounces, of converting the brutish realities of the analog world into pristine ones and zeros. Both hardware and software solutions exist, though by far the most common are those done in a snippet of code.

Surf the net to sample various approaches to debouncing. Most are pretty lame. Few are based on experimental bounce parameters. A medley of anecdotal tales passed around the newsgroups substitute for empirical evidence.

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