I2S Interface Specifications
One I2S port is provided by the J7 board-to-board connector interface.
See also: Audio Interface in the Expansion Board Design Guide, and I2S Interface in the Expansion Board Hardware Datasheet.
I2S Available Formats
The I2S formats listed below have not been verified and are subject to change.
Notes :
All Bits/Sample in the following tables are 16,24. Right justified is not supported. |
Priority 1
Mode | Frame-rate | Number of slots | Frame to data offset | Frame polarity | Frame width | Frame rate inaccuracy | Notes |
I2S master | 192K,96K, 48K, 16K, 8K | 2 | 1 | 0-left,
1-right | 50/50 | 0% | Standard I2S protocol. 50% duty |
PCM slave -SFS | 192K,96K, 48K, 44.1K, 16K, 8K | 192kHz: 2
96 kHz: 4
All else: 1 to 6 | 0 | High | |||
PCM slave - LFS | 192K, 96K, 48K, 44.1K, 16K,8K | 192 kHz: 2 96 kHz: 4 All else: 1 to 6 | 0 | High | 0% | ||
PCM master -SFS | 192K, 96K, 48K, 16K, 8K | 192 kHz: 2
All else: 1 to 4 | 0 | High | 1 bit clock wide | 0% | Rising edge frame sensitive. Design supports more frame- to-data offset options. |
PCM master - LFS | 192K, 96K, 48K, 16K, 8K | 92 kHz: 2
All else: 1 to 4 | 0 | High | 1-bit to n-bit clocks | 0% | Design supports width > 1 slot. |
Priority 2
Mode | Frame-rate | Number of slots | Frame to data offset | Frame polarity | Frame width | Frame rate inaccuracy | Notes |
Left justified master | 192K,96K, 48K | 2 | 0 | 0-left,
1-right | 50/50 | 0% | Design supports flipping polarity on the frame signal. |
Priority 3
Mode | Frame-rate | Number of slots | Frame to data offset | Frame polarity | Frame width | Frame rate inaccuracy | Notes |
I2S slave | 192K,96K, 48K,44.1K | 2 | 0 | 0-left,
1-right | 50/50 | 0% | |
Left justified slave | 192K,96K, 48K | 2 | 0 | 0-left,
1-right | 50/50 | 0% |
Digital microphone ports
The Intel® Joule™ module supports microphones that use the PDM digital microphone standard and attached to the module through the AVS_M interface. Two microphones can share one data line by using time domain multiplexing to the two slots.
PDM microphones are enabled and disabled by the clock signal. Absence of clock signal will switch microphone to sleep mode, which can be utilized in system power management.
Additionally the microphones can be power-gated to cut the power consumption to zero when microphones are not used.