Microchip Technology IS2083 Series Applications Design Manual Download

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2021 Microchip Technology Inc.

DS00003118C-Page 26

AN3118

FIGURE 27:

LDAC CODEC

The details of LDAC Application can be found in

Appendix G: “LDAC Application”

2.11

Concert Mode

Two or more speakers are used in Concert mode. One
speaker works as the central and the rest as
secondaries, connected to the central through
Bluetooth. The central is connected to a Bluetooth-
enabled streaming device through Bluetooth (such as
a smartphone) or to an AUX-In cable.

Figure 1

and

Figure 2

illustrate a typical Concert mode application.

The audio packets are SBC encoded (it is also possible
to use AAC encoded audio packets, refer to

Appendix

N: “Enabling AAC encoding in Concert/stereo
mode”

) with medium quality setting, and the audio

packet is not ACKed by peripheral. There is no
guaranteed feedback mechanism between
secondaries and the central. The button press on the
central is communicated to the peripheral, similarly, the
button press on the peripheral is communicated to the
central. It follows the same procedure of transmission
as a Bluetooth packet received by the central. The
AUX-In audio to a peripheral speaker plays on the
peripheral speaker only. It is not transmitted to the
central speaker.
The auto-reconnect feature has been enabled in
Concert mode; that is, upon the power cycle of the
central and peripheral, they reconnect. For more
details, refer to

Appendix K: “Auto Reconnection”

The MSPK central and peripheral use an access code
so they can connect with each other. A general access
code is used to add a new peripheral to a central while
a dedicated access code is used to resume the group
after the power cycle. The endless grouping
mechanism is using one or both access codes to allow
the central to add secondaries endlessly. For more
details, refer to

Appendix T: “Concert Mode Endless

Grouping”

2.12

Stereo Mode

Two speakers are used in Stereo mode. One speaker
works as a central and another as a peripheral
connected to the central through Bluetooth. The central
speaker is connected to a Bluetooth-enabled
streaming device through Bluetooth or through an
AUX-In cable to an audio streaming device.

Figure 4

and

Figure 5

illustrate a typical Stereo mode

application. The audio packets are SBC-encoded (it is
also possible to use AAC-encoded audio packets, refer
to

Appendix N: “Enabling AAC encoding in

Concert/stereo mode”

with a high quality setting and

every packet is ACKed by peripheral. The lost packet
or NACKed packet is re-transmitted by the central. The
button press is synchronized on both the central and
peripheral; in other words, play, pause, volume, up/
down button press on central and peripheral speaker
has a similar effect. The AUX-In audio is SBC-encoded
with high quality settings by the central. It follows the
same procedure of transmission as the Bluetooth
packet received by the central. The AUX-In audio on
the peripheral speaker plays on the peripheral speaker
and is not transmitted to the central speaker. The auto-
reconnect feature is enabled in Stereo mode; that is,
upon the power cycle of the central and peripheral, they
reconnect. For more details, refer to

Appendix K:

“Auto Reconnection”

2.12.1

TOGGLING BLUETOOTH AND AUX-
IN AUDIO

The audio source can be toggled by toggle button on
the Microchip Bluetooth Audio app (see

Figure 14

Note:

By default, LDAC functionality is enabled in the firmware but supported only on IS2083BM-2L2 device.