3 * <http://bugs.libre-riscv.org/show_bug.cgi?id=12>
4 * <https://opencores.org/project,ac97>
5 * <https://en.wikipedia.org/wiki/AC%2797>
7 Question: how does AC97 fit in with [[I2S]]?
11 * <https://numato.com/product/lm4550-ac97-stereo-audio-codec-expansion-module>