Created on 2012-11-09 00:19:00

HSP

HSP is the “Head Set Profile.” This profile supports only low bit rate, “voice-quality” audio, using the CVSD codec at 8 kHz sample rate or the HSP 1.6 "wideband speech" mSBC codec at 16 kHz. This profile is used for phone-to-headset communication.

Roles

Supported roles are AG “Audio Gateway” (the phone) and HS “Headset”.

Audio

Audio flows in a duplex (bi-directional) mode, connecting the Audio Gateway device to the Headset device.

Actions

A subset of AT commands are also supported for phone operations.

HFP

HFP is the “Hands Free Profile.” This profile supports only low bit rate, “voice-quality” audio, using the CVSD codec at 8 kHz sample rate or the HSP 1.6 "wideband speech" mSBC codec at 16 kHz*. This profile is used for phone-to-headset communication and for phone-to-car kit hands free communication.

Roles

Supported roles are AG “Audio Gateway” (the phone) and HF “Hands Free” (the headset or car kit mic/speaker).

Audio

Audio flows in a duplex (bi-directional) mode, connecting the Audio Gateway device to the Hands Free device.

Actions

A subset of AT commands are also supported for phone operations. Compared to HSP, HFP provides a few more AT commands for hands-free convenience, such as last number redial.

A2DP

A2DP is the “Advanced Audio Distribution Profile.” This profile supports higher bit rate, higher performance stereo audio. The SBC codec is mandatory; codecs such as mp3, AAC, apt-X and others are optionally supported.

Roles

APx supported profile roles are “source” (transmitting audio) and “sink” (receiving audio). Audio is distributed in one direction only, from the source device to the sink device.

Audio

APx supports the mandatory SBC and the optional apt-X codecs. In A2DP Source, the APx Bluetooth transmitter mutes the audio when the average signal level falls below –54 dBFS for more than 1 second. We recommend maintaining test levels above –54 dBFS for meaningful results.

AVRCP

AVRCP is the “Audio/Video Remote Control Profile.” This profile is used in conjunction with A2DP, and provides “transport” controls such as Play, Pause, Reverse, Forward, etc.

Roles

Supported profile roles are “controller” and “target.”