The WM977 AMR is an audio-only daughter card implementation of the Intel Audio Modem Riser (AMR) Rev 1.1 specification. This card can also be used in systems supporting the ACR 1. specification.
The design supports the connectivity requirements of a typical sound
card. Inputs include Phone, AUX, Video, CD (Mitsumi and Sony types) and Mic1/2. Outputs include Line Out, Line Level Out, Mono and Headphones and a digital SPDIF output for interfacing to external digital audio equipment.
The Audio Codec used in the design is the WM977 Stereo Audio Codec. The WM977 is fully compliant with Intel's AC?97 Rev 2.1 Codec specification and supports primary/secondary ID selection as well as variable audio and modem sample rates with the additional function of a digital SPDIF output.
