STLC2416

20/27

When spi_io from ADNS_2030 is driving, spi_rxd should be active, while spi_txd is set as a tri-state high

impedance input.

For a read operation, the Bluetooth spi_txd is put in high impedance state after the reception of the ad-

dress.

Note that this feature works independently of the SPI mode, supporting other combinations.

In this case, the devices are connected as described in the figure below.

Figure 7.

8.2.2

Feature description: 32 bit SPI

One application is a Bluetooth stereo headset. In this application, the audio samples are received from the

emitter through the air using the Bluetooth baseband with ACL packets. The samples are decoded by the

embedded ARM CPU (the samples were encoded, for compression, in SBC or MP3 format) and then sent

to a stereo codec though the SPI interface. The application is described in the figure below.

Figure 8.

To support this application, the data size is 32 bits. The 32 bits support is implemented for both transmit

and receive.

8.3 I2C Interface

Used to access I2C peripherals.

The interface is a fast master I2C; it has full control of the interface at all times. I2C slave functionality is

not supported.

STLC2416

Agilent ADNS-2030

spi_clk

spi_frm

spi_txd

spi_rxd

spi_clk

spi_io

SPI slave mode 32 bits

spi_frm

spi_clk

STw5094A CODEC

stereo headset

spi_txd

spi_r xd

32 spi_clk

16 spi_clk

STLC2416

Bluetooth

reception

SPI master mode 32 bits