BC41B143A-DS-002PD Datasheet, PDF (68/89 Pages) List of Unclassifed Manufacturers – BlueCore 4-ROM CSP EDR Single Chip Bluetooth v2.0 + EDR System

Device Terminal Descriptions
11.7 Audio PCM Interface
Pulse Code Modulation (PCM) is a standard method used to digitise audio (particularly voice) patterns for
transmission over digital communication channels. Through its PCM interface, BlueCore4-ROM CSP has
hardware support for continual transmission and reception of PCM data, so reducing processor overhead for
wireless headset applications. BlueCore4-ROM CSP offers a bi-directional digital audio interface that routes
directly into the baseband layer of the on-chip firmware. It does not pass through the HCI protocol layer.
Hardware on BlueCore4-ROM CSP allows the data to be sent to and received from a SCO connection.
Up to three SCO connections can be supported by the PCM interface at any one time⁽¹⁾.
BlueCore4-ROM CSP can operate as the PCM interface Master generating an output clock of 128, 256 or
512kHz. When configured as PCM interface slave it can operate with an input clock up to 2048kHz.
BlueCore4-ROM CSP is compatible with a variety of clock formats, including Long Frame Sync, Short Frame
Sync and GCI timing environments.
It supports 13 or 16-bit linear, 8-bit μ-law or A-law companded sample formats at 8ksamples/s, and can receive
and transmit on any selection of three of the first four slots following PCM_SYNC. The PCM configuration options
are enabled by setting the PS Key PS KEY_PCM_CONFIG.
BlueCore4-ROM CSP interfaces directly to PCM audio devices including the following:
! Qualcomm MSM 3000 series and MSM 5000 series CDMA baseband devices
! OKI MSM7705 four channel A-law and μ-law CODEC
! Motorola MC145481 8-bit A-law and μ-law CODEC
! Motorola MC145483 13-bit linear CODEC
! STW 5093 and 5094 14-bit linear CODECs
! BlueCore4-ROM CSP is also compatible with the Motorola SSI™ interface
Note:
(1) _{Subject to firmware support. Contact CSR for current status.}
11.7.1 PCM Interface Master/Slave
When configured as the Master of the PCM interface, BlueCore4-ROM CSP generates PCM_CLK and
PCM_SYNC.
BlueCore4-ROM
PCM_OUT
PCM_IN
PCM_CLK
PCM_SYNC
128/256/512kHz
8kHz
Figure 11.17: BlueCore4-ROM CSP as PCM Interface Master
When configured as the Slave of the PCM interface, BlueCore4-ROM accepts PCM_CLK rates up to 2048kHz.
BC41B143A-ds-002Pd
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© Cambridge Silicon Radio Limited 2005
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