[jacquesm]

> Tandy chose it for the TRS-80 Color Computer and sacrificed dedicated sound generation hardware for it to keep costs down.

The result of that though is an excellent example of 'software eating the world' and allowed for a whole pile of other tricks to be pulled (in software!) that would have required more circuitry in other computers. For instance, the tape interface used it, as well as the joystick interface. If you were a bit more adventurous you could use it for analog in as well as analog out.