CYW4343X
8. Bluetooth Baseband Core
The Bluetooth Baseband Core (BBC) implements all of the time-critical functions required for high-performance Bluetooth operation.
The BBC manages the buffering, segmentation, and routing of data for all connections. It also buffers data that passes through it,
handles data flow control, schedules SCO/ACL TX/RX transactions, monitors Bluetooth slot usage, optimally segments and pack-
ages data into baseband packets, manages connection status indicators, and composes and decodes HCI packets. In addition to
these functions, it independently handles HCI event types and HCI command types.
The following transmit and receive functions are also implemented in the BBC hardware to increase the reliability and security of
data before sending and receiving it over the air:
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Symbol timing recovery, data deframing, forward error correction (FEC), header error control (HEC), cyclic redundancy
check (CRC), data decryption, and data dewhitening in the receiver.
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Data framing, FEC generation, HEC generation, CRC generation, key generation, data encryption, and data whitening in
the transmitter.
8.1 Bluetooth 4.1 Features
The BBC supports all Bluetooth 4.1 features, with the following benefits:
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Dual-mode classic Bluetooth and classic Low Energy (BT and BLE) operation.
Low energy physical layer
Low energy link layer
Enhancements to HCI for low energy
Low energy direct test mode
128 AES-CCM secure connection for both BT and BLE
Note: The CYW4343X is compatible with the Bluetooth Low Energy operating mode, which provides a dramatic reduction in the power
consumption of the Bluetooth radio and baseband. The primary application for this mode is to provide support for low data rate
devices, such as sensors and remote controls.
8.2 Link Control Layer
The link control layer is part of the Bluetooth link control functions that are implemented in dedicated logic in the link control unit
(LCU). This layer contains the command controller that takes commands from the software, and other controllers that are activated
or configured by the command controller, to perform the link control tasks. Each task performs a different state in the Bluetooth link
controller.
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Major states:
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Standby
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Connection
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Substates:
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Page
Page Scan
Inquiry
Inquiry Scan
Sniff
BLE Adv
BLE Scan/Initiation
8.3 Test Mode Support
The CYW4343X fully supports Bluetooth Test mode as described in Part I:1 of the Specification of the Bluetooth System Version 3.0.
This includes the transmitter tests, normal and delayed loopback tests, and reduced hopping sequence.
In addition to the standard Bluetooth Test Mode, the CYW4343X also supports enhanced testing features to simplify RF debugging
and qualification as well as type-approval testing. These features include:
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Fixed frequency carrier-wave (unmodulated) transmission
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Simplifies some type-approval measurements (Japan)
Aids in transmitter performance analysis
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Document No. 002-14797 Rev. *H
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