Abstract:
Systems and methods for handling silence in audio streams are disclosed. In one aspect, a transmitter detects a halt in an audio stream. After detection of the halt in the audio stream, the transmitter embeds a silence signal into the audio stream and transmits the silence signal to associated receivers. The associated receivers may respond to the embedded silence signal by “playing” silence or by using the silence signal to activate a silence protocol. In either event, the associated receivers do not receive the original audio halt and do not produce an unwanted audio artifact.
Abstract:
A flow control protocol for an audio bus is disclosed. In an exemplary aspect, an audio source may push content to an audio sink over one or more cascaded audio bus segments or links. The audio source will send an indication to the audio sink that data is coming, and the audio sink should manipulate the data accordingly. Conversely, the audio source may also send an indication to the audio sink that, in a particular sample-event in a particular future sample-window, no data is present and the audio sink may disregard any bits in the corresponding sample-event. In another exemplary aspect, the audio sink may request data from the audio source with a receive ready indication. The audio source then sends data in a corresponding time slot for processing by the audio sink. Likewise, the audio sink may provide an indication that the audio sink cannot accept more data through a negative receive ready indication.
Abstract:
Time-constrained data copying between storage media is disclosed. When an electronic device is engaged in real-time operations, multiple data blocks may need to be copied from one storage medium to another storage medium within certain time constraints. In this regard, a data port is operatively controlled by a plurality of registers of a first register bank. The plurality of registers is copied from the first register bank to a second register bank within a temporal limit and while the data port remains under control of the plurality of registers being copied. By copying the plurality of registers within the temporal limit, it is possible to prevent operational interruption in the data port and reduce bandwidth overhead associated with the register copying operation.
Abstract:
Control circuits for generating output enable signals are disclosed. In one aspect, a control circuit is provided that employs combinatorial logic to generate an output enable signal that meets timing constraints using a standard clock signal, a feedback clock signal based on the standard clock signal, and a single data rate (SDR) data output stream. The control circuit includes a double data rate (DDR) conversion circuit configured to generate a DDR output stream based on a received SDR output stream. The control circuit includes an output enable circuit configured to receive the standard clock signal, feedback clock signal, and DDR output stream, and to generate the output enable signal that is asserted and de-asserted according to the defined timing constraints. The control circuit is configured to generate an accurately timed output enable signal without the need for a fast clock signal in addition to the standard clock signal.
Abstract:
Delay circuits, and related systems and methods are disclosed. In one aspect, a delay circuit is provided that uses logic to delay accurately an output enable signal to reduce or avoid data hazards within a slave device. The delay circuit includes two shift register chains configured to receive an output enable in signal based on a slow clock. A first shift register chain is clocked by a positive edge of a fast clock, and provides a first strobe signal. A second shift register chain is clocked by a negative edge of the fast clock, and provides a second strobe signal. The logic uses the first and second strobe signals, and the output enable in signal, to provide a delayed output enable out signal. The delay circuit provides a highly accurate time delay for the output enable signal to reduce or avoid data hazards in an area and power efficient manner.
Abstract:
Full bandwidth communication buses are disclosed. While primarily focused on the Serial Low-power Inter-chip Media Bus (SLIMbus) communication bus, the concepts of the present disclosure may be extended to other communication buses. Exemplary aspects of the present disclosure utilize a reserved segment distribution code and a segment length to define a Segment Interval that is better-sized relative to raw data bits. By fitting the segment interval to the size of the raw data bits, bandwidth utilization is maximized, resulting in faster effective data transfers. Completion of such efficient data transfers may allow the communication bus to spend more time in a low-power mode and thus, conserve power. Additionally, such efficient data transfers may allow for better quality in presentation of multimedia content to the user.
Abstract:
Device identification generation in electronic devices to allow external control, such as selection or reprogramming, of device identification for bus communications identification, is disclosed. In this manner, device identifications of electronic devices coupled to a common communications bus in a system can be selected or reprogrammed to ensure they are unique to avoid bus communications collisions. In certain aspects, to select or reprogram a device identification in an electronic device, an external source can be electrically coupled to the electronic device. The external source closes a circuit with a device identification generation circuit in the electronic device. The closed circuit provides a desired electrical characteristic detectable by the device identification generation circuit. The device identification generation circuit is configured to generate a device identification as a function of the detected electrical characteristics of the closed circuit from the external source.
Abstract:
Systems and methods for fast activation of slaves during wake up in an audio system allow a master device in an audio system such as a SOUNDWIRE audio system to send system and/or topology information to capable slave devices during a wake up window so that the slaves may start in an active mode rather than a safe mode. In the most recent proposed versions of SOUNDWIRE, there is a check PHY_Num phase. The systems for fast activation of slaves cause a negative differential line to be driven with an encoded signal by the master during a check PHY_Num phase where the encoded signal indicates a fast mode speed. Capable slaves may then begin in a fast mode rather than a safe (and slow) mode. Latency may be reduced by starting in a fast mode, which may improve the user's audio experience.
Abstract:
Systems, methods, apparatus and techniques are described that provide point-to-point capabilities without the expected increase in input/output pad usage. In some examples, point-to-point data lines are provided between a host and multiple slave devices and timing of communication is controlled using a clock signal shared by the multiple slave devices. An apparatus has a plurality of bus master circuits configured to control point-to-point communication with corresponding slave devices and a clock generation circuit configured to provide pulses in a serial bus clock signal when one or more bus master circuits are in an active state, and further to idle the serial bus clock signal when all bus master circuits are idle. Each bus master circuit may be configured to communicate with its corresponding slave device in accordance with the timing provided by the serial bus clock signal that is transmitted over a common clock line to each slave device.
Abstract:
Systems and methods for essentially continuous audio flow for Internet of Things (IoT) devices during power mode transitions contemplate an audio bus, such as a SOUNDWIRE audio bus, to maintain an audio stream during a clock transition without having to tear down the audio stream as a new clock becomes active on the audio bus. By preserving the audio stream during such a transition, gaps in the audio are avoided resulting in better performance and end user experience.