HFP

Audio Agent supports the HFP profile (v1.7). The two HFP roles, Hands-Free unit (HF) and Audio Gateway (AG), are supported and can be enabled or disabled in the PROFILES config. Audio Agent allows up to 3 HF or AG connections. The configuration for this profile is stored in HFP_CONFIG.

Audio Agent supports 4 codecs: * Narrow Band (8kHz) * Wide Band Speech (16kHz) * cVc Handsfree Narrow Band (8kHz) * cVc Handsfree Wide Band (16kHz)

Please note that the use of Clear Voice Capture (cVc), which is an algorithm provided by Cambridge Silicon Radio (CSR) for echo and noise cancellation, requires a license key. Please contact info@blue-creation.com or your distributor for more information about cVc.

Use the CALL command to initiate, answer, reject or transfer calls on the AG or HF (see HFP example).

When using the digital interface with I2S, Audio Agent re-samples the audio if the required digital rate (WCLK) is superior or equal to 44100 Hz. Otherwise you need to match the sample rate of the codec (ie. 8kHz or 16 kHz).

Since the audio is a mono signal, the input is always taken on the left channel (Analog or Digital). The output is stereo (same signal copied on both left and right channel).