User's Manual

Table Of Contents
S3C2450X RISC MICROPROCESSOR IIS MULTI AUDIO INTERFACE
26-1
26 IIS MULTI AUDIO INTERFACE
1 OVERVIEW
IIS (Inter-IC Sound) is one of the popular digital audio interface. The bus has only to handle audio data, while the
other signals, such as sub-coding and control, are transferred separately. Surely, it is possible to transmit data
between two IIS bus. To minimize the number of pins required and to keep wiring simple, basically, a 3-line serial
bus is used consisting of a line for two time-multiplexed data channels, a word select line and a clock line.
IIS interface transmits or receives sound data from external stereo audio codec. For transmitting and receiving
data, three 32x16 TXFIFOs(First-In-First-Out) and one 32x16 RXFIFO data structures are included and DMA
transfer mode for transmitting or receiving samples can be supported. IIS-specific clock can be supplied from
internal system clock controller through IIS clock divider or direct clock source.
2 FEATURE
Up to 5.1ch IIS-bus for audio interface with DMA-based operation
Serial, 8/16/24 bit per channel data transfers
Supports IIS, MSB-justified and LSB-justified data format
Three 32-bit width 16 depth Tx FIFOs, One 32-bit width 16 depth Rx FIFO
3 SIGNALS
Name Direction Description
I2SLRCLK Input/Output IIS Multi Audio channel select(word select) clock
I2SSCLK Input/Output IIS Multi Audio serial clock(bit clock)
I2SCDCLK Input/Output IIS Multi Audio Codec clock
I2SSDI Input IIS Multi Audio serial data input
I2SSDO Output IIS Multi Audio serial data output 0
I2SSDO_1 Output IIS Multi Audio serial data output 1
I2SSDO_2 Output IIS Multi Audio serial data output 2