The Mockingboard, introduced around 1981, was a sound card for the Apple II
series of computers. It has dual AY-3-8910 chips on it, providing a total
of 6 channels of square-wave sound, plus noise and envelope effects.
It was only used by a smallish subset of contemporary games, but it can
be fun to play with when doing retro-coding.
You should also see my
Raspberry Pi-Chiptune player page; I developed that board (which is
essentially a Mockingboard for the Raspberry Pi) while waiting to buy
one for my Apple II.
The Kerbal Space Program theme. In case you are curious the
"game" sequence tacked on the end is from my BASIC version that
you can find here
(sadly it currently only has a 1-bit speaker
rendition of the song)
You can see more of my projects that use the Mockingboard on my