User's Manual

FLC-BTM805 Datasheet
Flaircomm Microelectronics Confidential
-15-
Note: Pull-up (PU) and pull-down (PD) default to weak values unless specified otherwise.
4.3 Audio Interfaces
BTM805 has two digital audio interfaces that are configurable as either PCM or I
2
S ports.
4.3.1 PCM Interface
There are two audio interfaces. Each can be independently configured as an I
2
S or a PCM port. The
PCM1 interface also shares the same physical set of pins with the SPI interface as described in the
Device Terminal Functions section. Either interface is selected using SPI_PCM#_SEL:
 SPI_PCM#_SEL=1 selects SPI
 SPI_PCM#_SEL=0 selects PCM
Important Note:
The PCM description refers to both PCM1 or PCM2.
The audio PCM interface on the BTM805 supports:
 Continuous transmission and reception of PCM encoded audio data over Bluetooth.
 Processor overhead reduction through hardware support for continual transmission and
reception of PCM data.
 A bidirectional digital audio interface that routes directly into the baseband layer of the
firmware. It does not pass though the HCI protocol layer.
 Hardware on the BTM805 for sending data to and from a SCO connection.
 Up to 3 SCO connections on the PCM interface at any one time.
 PCM interface master, generating PCM_SYNC and PCM_CLK.
 PCM interface slave, accepting externally generated PCM_SYNC and PCM_CLK.
 Various clock formats including:
 Long Frame Sync
 Short Frame Sync
 GCI timing environments
 13-bit or 16-bit liner, 8-bitμ -law or A-law companded sample formats.
 Receives and transmits on any selection of 3 of the first 4 slots following PCM_SYNC.
The PCM configuration options are enabled by setting the PS Key PSKEY_PCM_CONFIG32.
4.3.1 .1 PCM Interface Master/Slave
When configured as the master of the PCM interface, BTM805 generates PCM_CLK and
PCM_SYNC.