Audio Streaming

Description

The Audio Streaming application uses the SPARK Wireless Core to implement a bidirectional audio stream. It is a good starting point for anyone wishing to use the SPARK Audio Core. Audio data is recorded at the source and played back at the destination through the device’s analog ports.

Behavior

In this application, the Coordinator transmits a 48 kHz/16 bits stereo audio to the Node. The Node also transmits a 16 kHz/16 bits mono audio stream back to the Coordinator.

Each device is assigned communication timeslots. The Coordinator needs four times as many timeslots as the Node because its bandwidth requirements are higher.

The following diagram illustrates the general structure of the schedule used in this application.

Audio Streaming schedule

Figure 11: Audio Streaming application’s schedule.

Once the application is started, the Coordinator and Node record the audio signal from an audio source on their Line-In jack (blue) and sends it over-the-air to the other device to be played back on a speaker or headphones connected to their Headphones jack (black).

Coordinator Device

  • SW1 and SW2 are used to turn the volume up and down respectively. By default, the volume is at the maximum level.

  • LED0 toggles every time a packet is successfully transmitted to the Node (almost always on because of the high packet rate).

  • LED1 toggles every time a packet is successfully received from the Node (almost always on because of the high packet rate).

Interface

Name

Description

SW1

Volume Up

Raises the volume (default at 100%).

SW2

Volume Down

Lowers the volume.

LED0

Transmission Success

Toggle LED when a wireless transmission is successful.

LED1

Reception Success

Toggle LED when a wireless reception is successful.

LED2

N/A

N/A

Node Device

  • SW1 and SW2 are used to turn the volume up and down respectively. By default, the volume is at the maximum level.

  • LED0 toggles every time a packet is successfully transmitted to the Coordinator (almost always on because of the high packet rate).

  • LED1 toggles every time a packet is successfully received from the Coordinator (almost always on because of the high packet rate).

Interface

Name

Description

SW1

Volume Up

Raises the volume (default at 100%).

SW2

Volume Down

Lowers the volume.

LED0

Transmission Success

Toggle LED when a wireless transmission is successful.

LED1

Reception Success

Toggle LED when a wireless reception is successful.

LED2

N/A

N/A

Configuration

This application does not require specific configurations.