CYW20732A0
1. Functional Description
1.1 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 data routing for all connections. It also buffers data that passes through it, handles
data flow control, schedules ACL TX/RX transactions, monitors Bluetooth slot usage, optimally segments and packages 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 TX/RX data reliability and security
before sending over the air:
■ Receive Functions: symbol timing recovery, data deframing, forward error correction (FEC), header error control (HEC), cyclic
redundancy check (CRC), data decryption, and data dewhitening.
■ Transmit Functions: data framing, FEC generation, HEC generation, CRC generation, link key generation, data encryption, and
data whitening.
1.1.1 Frequency Hopping Generator
The frequency hopping sequence generator selects the correct hopping channel number depending on the link controller state,
Bluetooth clock, and device address.
1.1.2 E0 Encryption
The encryption key and the encryption engine are implemented using dedicated hardware to reduce software complexity and provide
minimal processor intervention.
1.1.3 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 consists of the Command Controller, which takes software commands, and other controllers that are activated or configured
by the Command Controller to perform the link control tasks. Each task performs a different Bluetooth link controller state. STANDBY
and CONNECTION are the two major states. In addition, there are five substates: page, page scan, inquiry, and inquiry scan.
1.1.4 Adaptive Frequency Hopping
The CYW20732 gathers link quality statistics on a channel-by-channel basis to facilitate channel assessment and channel map
selection. The link quality is determined by using both RF and baseband signal processing to provide a more accurate frequency hop
map.
1.1.5 Bluetooth Low Energy Profiles
The CYW20732 supports Bluetooth low-energy, including the following profiles that are supported1 in ROM:
■ Battery status
■ Blood pressure monitor
■ Find me
■ Heart rate monitor
■ Proximity
■ Thermometer
■ Weight scale
■ Time
The following additional profiles can be supported1 from RAM:
■ Blood glucose monitor
■ Temperature alarm
■ Location
■ Custom profile
1. Full qualification and use of these profiles may require firmware updates from Cypress. Some of these profiles are under development/approval at the Bluetooth SIG
and conformity with the final approved version is pending. Contact your supplier for updates and the latest list of profiles.
Document Number: 002-14837 Rev. *L
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