PRELIMINARY
CYW20710
3.7 Adaptive Frequency Hopping
The CYW20710 supports host channel classification and dynamic channel classification Adaptive Frequency Hopping (AFH)
schemes, as defined in the Bluetooth specification.
Host channel classification enables the host to set a predefined hopping map for the device to follow.
If dynamic channel classification is enabled, the device gathers link quality statistics on a channel-by-channel basis to facilitate channel
assessment and channel map selection. To provide a more accurate frequency hop map, link quality is determined using both RF and
baseband signal processing.
3.8 Collaborative Coexistence
The CYW20710 provides extensions and collaborative coexistence to the standard Bluetooth AFH for direct communication with
WLAN devices. Collaborative coexistence enables WLAN and Bluetooth to operate simultaneously in a single device. The device
supports industry-standard coexistence signaling, including 802.15.2, and supports Cypress and third-party WLAN solutions.
Using a multitiered prioritization approach, relative priorities between data types and applications can be set. This approach maximizes
the performance-WLAN data throughput vs. voice quality vs. link performance.
A PA shutdown pin is available to allow full external control of the RF output for other types of coexistence, such as WIMAX.
3.9 Serial Enhanced Coexistence Interface
The Serial Enhanced Coexistence Interface (Serial ECI or SECI) is a proprietary Cypress interface between Cypress WLAN devices
and Bluetooth devices. It is an optional replacement to the legacy 3- or 4-wire coexistence feature, which is also available.
The following key features are associated with the interface:
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Enhanced coexistence data can be exchanged over SECI_IN and SECI_OUT.
It supports generic UART communication between WLAN and Bluetooth devices.
To conserve power, it is disabled when inactive.
It supports automatic resynchronizaton upon waking from sleep mode.
It supports a baud rate of up to 4 Mbps.
3.9.1 SECI Advantages
The advantages of the SECI over the legacy 3-wire coexistence interface are:
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Only two wires are required: SECI_IN and SECI_OUT.
Up to 48-bits of coexistence data can be exchanged.
Previous Cypress stand-alone Bluetooth devices such as the CYW2070 supported only a 3-wire or 4-wire coexistence interface.
Previous Cypress WLAN and Bluetooth combination devices such as the CYW4325, CYW4329, and CYW4330 support an internal
parallel enhanced coexistence interface for more efficient WLAN and Bluetooth information exchange. The SECI allows enhanced
coexistence information to be passed to a companion Cypress WLAN chip through a serial interface using fewer I/O than the 3-wire
coexistence scheme.
The 48-bits of the SECI significantly enhance WLAN and Bluetooth coexistence by sharing such information as frequencies used and
radio usage times. The exact contents of the SECI are Cypress confidential.
3.9.2 SECI I/O
The CYW20710 does not have dedicated SECI_IN or SECI_OUT pins, but the two pin functions can be mapped to the following digital
I/O: the UART, GPIO, SPIM (or BSC), PCM, and COEX pins. Pin function mapping is controlled by the config file that is either stored
in NVRAM or downloaded directly into on-chip RAM from the host.
Document No. 002-14804 Rev. *H
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CYPRESS [ CYPRESS ]
