I2S Interface (Digital Audio); General Purpose Input/Output (Gpio) - Sierra Wireless AirPrime BX3100 Hardware Integration Manual

Hardware Integration Guide
Rev 3 Sep.18

4.5 I2S Interface (Digital Audio)

Note: Interface support is forthcoming.
The AirPrime BX310x provides a 4-wire I
to transfer serial digital audio to or from an external stereo DAC/ADC, and supports
the following features:
• Modes—Master, Slave
• Transmission format—Full duplex, Half duplex
• Resolution (bits per frame)—8, 16, 32, 40, 48
• Channels—Input, Output
• Bit clock—10 kHz–40 MHz
• Supported audio interfaces (forthcoming)—PDM (Pulse Density Modulation),
BT PCM (Pulse Code Modulation)
The interface uses the pins indicated in
Table 4-5: I2S Interface Pins
Pin Signal name Direction
16 I2S_MCLK
24 I2S_DO
25 I2S_DI
26 I2S_LRCLK
27 I2S_BCLK
a. Leave open any pins that are not used.
b. Signal direction with respect to the module.

4.6 General Purpose Input/Output (GPIO)

The AirPrime BX310x defines several GPIOs for customer use, as described in
Table 4-6 and Table 4-7.
Note: The pins carrying the 'Alternate function' GPIOs are multi-function. The alternate inter-
faces (SDIO or SPI) can be selected via an AT command.
Table 4-6: GPIO Pins (Dedicated)
Pin Signal Name Direction
14 GPIO(5)
35 GPIO(27)
a. Leave open any pins that are not used.
b. Pulled high internally
c. Internal configuration—no internal pull-ups
2
S (digital audio) interface that can be used
Table 4-5.
a
b
Function
O I2S MasterClock
O I2S Data Out
I I2S Data In
I/O I2S Left-Right Clock (Word Select)
I/O I2S Bit Clock
a
Default State
b
I/O Pull high
c
I/O No pull
18
Voltage Level
VDD_PADS_BB
Function Voltage Level
General purpose I/O VDD_PADS_BB
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