Patent ID: 9076491
Filing Date: 2015-07-07
Classification: G11B

Abstract:
1. An audio data outputting apparatus for receiving, from a host apparatus at predetermined frame periods, audio data supplied via a communication bus, performing processing, and then outputting the audio data, the audio data outputting apparatus comprising: a receiving portion which has a first-in, first-out reception buffer, and performs, in accordance with a request for output transmitted from the host apparatus to the audio data outputting apparatus via the communication bus at the predetermined frame periods, a receiving operation of receiving a plurality of samples of audio data for a plurality of channels transmitted from the host apparatus via the communication bus, and writing the received audio data for the channels into the reception buffer; a reproducing portion which has a first-in, first-out reproduction buffer and performs a reproducing operation of reading out one sample of the audio data for the channels stored in the reproduction buffer to output the read data at predetermined sampling periods; a processor which controls at least part of the audio data outputting apparatus; and a controller which controls respective operations of the receiving portion and the reproducing portion in accordance with an instruction from the processor, the processor providing, when receiving, from the host apparatus via the communication bus, a parameter relating to audio data which is to be received, the parameter to the controller; and instructing, when receiving, from the host apparatus via the communication bus, an instruction to start output of audio data, the controller to start operating; wherein the controller is configured for clearing, in accordance with the instruction from the processor to start operating, the reception buffer and the reproduction buffer, enabling the receiving operation of the receiving portion, and stopping the reproducing operation of the reproducing portion, and thereafter at the predetermined frame periods, transferring, if the receiving portion has received audio data with the reproducing operation of the reproducing portion being stopped, the received audio data from the reception buffer to the reproduction buffer, and instructing, when audio data stored in the reproduction buffer reaches a threshold amount, the reproducing portion to start the reproducing operation; transferring, if the receiving portion has received audio data with the reproducing portion being in the reproducing operation, the received audio data from the reception buffer to the reproduction buffer; stopping, if the receiving portion is not receiving audio data, the reproducing operation of the reproducing portion; and stopping, if the receiving portion has received audio data with the reproduction buffer being full or short of data, the reproducing operation of the reproducing portion, clearing audio data stored in the reproduction buffer, and transferring the received audio data from the reception buffer to the reproduction buffer as an automatic recovery process.