The McASP functions as a general-purpose audio serial port optimized for the needs of multichannel audio applications. Depending on the implementation, the McASP may be useful for time-division multiplexed stream, Inter-Integrated Sound protocols, and intercomponent digital audio interface transmission. However, some implementations are limited to supporting just the Inter-Integrated Sound protocol.
The McASP consists of transmit and receive sections that may operate synchronized, or completely independently with separate master clocks, bit clocks, and frame syncs, and using different transmit modes with different bit-stream formats. The McASP module also includes up to 16 serializers that can be individually enabled to either transmit or receive. In addition, all of the McASP pins can be configured as general-purpose input/output pins.
Features
Features of the McASP include:
Two independent clock generator modules for transmit and receive
*Clocking flexibility allows the McASP to receive and transmit at different rates. For example, the McASP can receive data at 48 kHz but output up-sampled data at 96 kHz or 192 kHz.
Independent transmit and receive modules, each includes:
*Programmable clock and frame sync generator
*TDM streams from 2 to 32, and 384 time slots
*Support for time slot sizes of 8, 12, 16, 20, 24, 28, and 32 bits
384-slot TDM with external digital audio interface receiver device
*For DIR reception, an external DIR receiver integrated circuit should be used with I2S output format and connected to the McASP receive section.
Extensive error checking and recovery
*Transmit underruns and receiver overruns due to the system not meeting real-time requirements
*Early or late frame sync in TDM mode
*Out-of-range high-frequency master clock for both transmit and receive
*External error signal coming into the AMUTEIN input
*DMA error due to incorrect programming
Protocols
The McASP supports a wide variety of protocols.
Transmit section supports
*Wide variety of I2S and similar bit-stream formats
*TDM streams from 2 to 32 time slots
*S/PDIF, IEC60958-1, AES-3 formats
Receive section supports
*Wide variety of I2S and similar bit-stream formats
*TDM streams from 2 to 32 time slots
*TDM stream of 384 time slots specifically designed for easy interface to external digital interface receiver device transmitting DIR frames to McASP using the I2S protocol
The transmit and receive sections may each be individually programmed to support the following options on the basic serial protocol:
Programmable clock and frame sync polarity : ACLKR/X, AHCLKR/X and AFSR/X
