K60P100M100SF2RM Datasheet, PDF (1678/1809 Pages) Freescale Semiconductor, Inc – K60 Sub-Family Reference Manual

Introduction
• Asynchronous protocol
• Synchronous protocol
• Gated clock mode
• Synchronous protocol only
• I²S mode
• AC97 mode
• AC97 fixed mode (ACNT[FV] = 0)
• AC97 variable mode (ACNT[FV] = 1)
These modes can be programmed by several bits in the I²S control registers. The
following table lists these operating modes and some of the typical applications in which
they can be used:
Table 53-1. I²S Operating Modes
TX, RX Sections
Asynchronous
Asynchronous
Synchronous
Synchronous
Synchronous
Serial clock
Continuous
Continuous
Continuous
Continuous
Gated
Mode
Normal
Network
Normal
Network
Normal
Typical application
Multiple synchronous CODECs
TDM codec or DSP networks
Multiple synchronous codecs
TDM codec or DSP network
SPI-type devices: DSP to MCU
The transmit and receive sections of the I²S can be synchronous or asynchronous. In
synchronous mode, the transmitter and the receiver use a common clock and frame
synchronization signal. Masking of slots for transmit and receive section can differ in
synchronous mode. Also the RCR[RXBIT0, RSHFD] bits can continue affecting shifting-
in of received data in synchronous mode. In asynchronous mode, the transmitter and
receiver each has its own clock and frame synchronization signals. Continuous or gated
clock mode can be selected. In continuous mode, the clock runs continuously. In gated
clock mode, the clock is only functioning during transmission.
Normal or network mode can also be selected. In normal mode, the I²S functions with
one data word of I/O per frame. In network mode, any number from two to thirty-two
data words of I/O per frame can be used. Network mode is typically used in star time-
division-multiplex networks with other processors or codecs, allowing interface to time
division multiplexed networks without additional logic. Use of gated clock mode is not
allowed in network mode. These distinctions result in the basic operating modes that
allow the I²S to communicate with a wide variety of devices.
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K60 Sub-Family Reference Manual, Rev. 6, Nov 2011
Freescale Semiconductor, Inc.