PAN1326C Bluetooth Module
2 Overview
Product Specification Rev. 1.0
Page 15
2.6.2 Audio/Voice CODEC Interface
The codec interface is a fully-dedicated programmable serial port that provides the logic to
interface to several k
inds of PCM or I2S codec’s. PAN13x6C supports all voice coding schemes
required by Bluetooth specification
– Log PCM (A-Law or μ-Law) and Linear (CVSD). In
addition, module also supports transparent scheme:
•
Two voice channels
•
Master / slave modes
•
µ-Law, A-Law, Linear, Transparent coding schemes
•
Long and short frames
•
Different data sizes, order, and positions.
•
High rate PCM interface for EDR
•
Enlarged interface options to support a wider variety of codecs
•
PCM bus sharing
2.6.2.1 PCM Hardware Interface
The PCM interface is one implementation of the codec interface. It contains the following four
lines:
•
Clock
– configurable direction (input or output)
•
Frame Sync
– configurable direction (input or output)
•
Data In
– Input
•
Data Out
– Output/3-state
The Bluetooth device can be either the master of the interface where it generates the clock and
the frame-sync signals, or slave where it receives these two signals. The PCM interface is fully
configured by a vendor specific command.
For slave mode, clock input frequencies of up to 16 MHz are supported. At clock rates above 12
MHz, the maximum data burst size is 32 bits. For master mode, the CC2564C can generate any
clock frequency between 64 kHz and 6 MHz.
When the I2S bus is used in an application, Panasonic recommends adding a low pass filter
(series resistor and capacitor to GND) to the bus for better noise suppression. Connecting the
host μController/DSP directly with the module’s I2S interface is not recommended.
The suggested low pass filter component values are:
470 pF
120
Ω
2.6.2.2 Data Format
The data format is fully configurable:
•
The data length can be from 8 to 320 bits, in 1-bit increments, when working with two
channels, or up to 640 bits when using 1 channel. The Data length can be set
independently for each channel.
