Datasheet

Write-protection does not apply for accesses through an external debugger.

29.5.9 Analog Connections

Not applicable.

29.6 Functional Description

29.6.1 Principle of Operation

The I

S uses three or four communication lines for synchronous data transfer:

• SDm for receiving or transmitting in Serializer m (m=0..1)

• SCKn for the serial clock in Clock Unit n (n=0..1)

• FSn for the frame synchronization or I

S word select, identifying the beginning of each frame

• Optionally, MCKn to output an oversampling clock to an external codec

S data transfer is frame based, where a serial frame:

• Starts with the frame synchronization active edge, and

• Consists of 1 to 8 data slots, that are 8-, 16-, 24-, or 32-bit wide.

Each data slot is used to transfer one data sample of 8, 16, 18, 20, 24 or 32 bits.

Frame based data transfer is described in the following figure:

Figure 29-2. Data Format: Frames, Slot, Bits and Clocks

S supports multiple data formats such as:

• 32-, 24-, 20-, 18-, 16-, and 8-bit mono or stereo format

• 16- and 8-bit compact stereo format, with left and right samples packed in the same word to reduce

data transfers

SAM D21 Family

I2S - Inter-IC Sound Controller

Datasheet Complete

DS40001882D-page 629