The
harmony device uses the Crystal Semiconductor CS4215 16-Bit Multimedia Audio Codec or Analog Devices AD1849 SoundPort(R) Stereo Codec chip to implement the audio device interface described in
audio(4). This device is found on most HP PA-RISC workstations. The
harmony has a maximum precision of 16 bits and has a stereo input and stereo output.
On HP 9000/712 models
harmony also provides two additional channels for an add-on card with two fax/voice modems.
One of the hardware registers reflects the state of the CHI bus that is used to communicate with the codec and thus being sampled at a low accuracy secondary frequency (such as
timeout(9)) produces poor quality random bit stream that is fed into the entropy pool of
rnd(4).