Always-on detection systems
The present disclosure relates to a system for providing an acknowledgement output at an output transducer of a device in response to detection of a trigger signal. The system includes an input transducer, a signal processor, a main processor separate from the signal processor and an output driver. The signal processor monitors an input signal received at the signal processor from the input transducer and outputs an acknowledgement signal to the output driver if the received input signal corresponds to the trigger signal. The signal processor also outputs an interrupt signal to the main processor to cause the main processor to enter an active state. In this way an acknowledge output can rapidly be provided to a user of the system, as there is no need to wait until the main processor has entered its active state and processed the trigger signal.
1. A system for providing an acknowledgement output at a haptic output transducer of a device in response to detection of a trigger signal, the system comprising:
an input transducer;
a signal processor coupled to the input transducer;
a main processor separate from the signal processor;
an output driver; and
a memory, wherein the memory is configured to store one or more acknowledgement signals corresponding to the acknowledgement output, wherein the signal processor is configured to:
monitor an input signal received at the signal processor from the input transducer; and
if the received input signal corresponds to the trigger signal:
retrieve, from the memory, an acknowledgement signal comprising a haptic waveform corresponding to an acknowledge effect to be output by the haptic output transducer;
output the acknowledgement signal to the output driver to cause the output driver to drive the haptic output transducer to output the acknowledgement output; and
output an interrupt signal to the main processor to cause the main processor to enter an active state, wherein the main processor is configured to transmit the received input signal to a server for verification that the received input signal is a valid audio trigger.
2. A system according to claim 1 wherein the input transducer is an audio input transducer and wherein the signal processor is configured to monitor an audio input signal received at the signal processor from the audio input transducer.
3. A system according to claim 2 wherein the signal processor comprises an always-on audio detection system configured to monitor the audio input signal received at the signal processor from the audio input device.
4. A system according to claim 2 wherein the trigger signal is a voice command.
5. A system according to claim 2 further comprising a buffer, wherein the buffer is configured to store audio input received by the audio input transducer after the trigger signal has been received, and wherein the system is configured to transmit the contents of the buffer to the main processor after the main processor has entered its active state.
6. A system according to claim 1 wherein the one or more acknowledgement signals corresponding to the acknowledgement output further comprise one or more of:
an audio acknowledgement signal or waveform; and
a visual acknowledgement signal.
7. A system according to claim 1 wherein the memory is on-board memory of the signal processor.
8. A system according to claim 1 wherein the main processor is configured to enter an inactive state when not in use.
9. A method for providing an acknowledgement output at a haptic output transducer of a device in response to detection of a trigger signal, the method comprising:
monitoring, at a signal processor, an input signal received at the signal processor from an input transducer; and
if the received input signal corresponds to the trigger signal:
retrieving, from a memory of the device, an acknowledgement signal comprising a haptic waveform corresponding to an acknowledge effect to be output by the haptic output transducer;
outputting, from the signal processor, the acknowledgement signal to an output driver of the device to cause the output driver to drive the haptic output transducer to output the acknowledgement output;
outputting, from the signal processor, an interrupt signal, to cause a main processor of the device to enter an active state; and
transmitting, by the main processor, the received input signal to a server for verification that the received input signal is a valid audio trigger.
10. A method according to claim 9 wherein the input transducer is an audio input transducer, and wherein the method comprises monitoring, at the signal processor, an audio input signal received at the signal processor from the audio input transducer.
11. A method according to claim 10 wherein the trigger signal is a voice command.
12. A method according to claim 9 further comprising causing the main processor to enter an inactive state when not in use.