User's Manual

Bluetooth Transmit Data Module
Shanghai Ehong Technologies Inc
10. SPI interface
The synchronous serial port interface (SPI) is used for flash/debug the module only. It can not be
used for any user functionality. Please always design test points for this interface on the PCB in
case that the module is needed to re-flash or flash-in-field in manufacture.
11. PCM interface
PCM is a standard method used to digitize audio (particularly voice) for transmission over digital
communication channels. Through its PCM interface, the module has hardware support for
continual transmission and reception of PCM data, thus reducing processor overhead for
applications. The module 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 the module 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.
The module 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. The module is compatible with a variety of clock formats, including Long Frame Sync,
Short Frame Sync and GCI timing environments.