U31–u33 (ringback cadence registers), U34–u35 (dial tone timing register), U37–u45 (pulse dial registers) – Silicon Laboratories SI2493/57/34/15/04 User Manual

U31–u33 (ringback cadence registers), U34–u35 (dial tone timing register), U37–u45 (pulse dial registers) | An93 | Silicon Laboratories SI2493/57/34/15/04 User Manual | Page 101 / 304