2.4 SPI Bus

The module is a slave device that uses terminals SPI_MOSI, SPI_MISO, SPI_CLK and SPI_CSB. This interface is used for program firmware update.

Note: The designer should be aware that no security protection is built into the hardware or firmware associated with this port, so the terminals should not be permanently connected in a PC application.

2.5 Parallel PIO Port

Five lines of programmable bi-directional input/outputs (I/O) are provided. GPIO[1:5] are powered from VCC. The mode of these lines can be configured and the lines are accessed via S Registers 621 to 625.

Auxiliary functions available via these pins include an 8-bit ADC and an 8-bit DAC. This function is not implemented at this time.

2.6 PCM Codec Interface

PCM_OUT, PCM_IN, PCM_CLK and PCM_SYNC carry up to three bidirectional channels of voice data, each at 8K samples/s. The format of the PCM samples can be 8-bit A-law, 8-bit µ-law, 13-bit linear or 16-bit linear. The PCM_CLK and PCM_SYNC terminals can be configured as inputs or outputs, depending on whether the module is the Master or Slave of the PCM interface.

The blu2i module is compatible with the Motorola SSI TM interface and 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

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