Specifications

SLAA154
Interfacing the TLV320AIC12/13/14/15 Codec to the TMS320C5402™ DSP 3
An AIC12 device is defined a master or a slave on the basis of the origin of the FS and SCLK.
The AIC12 is a master if the FS and SCLK are generated by the AIC12 and both signals are the
outputs from the codec to the host processor or other codec devices. Otherwise, if the two
signals are inputs to the codec, the AIC12 is called a slave. Moreover, if only one AIC12
interfaces with a serial port of the host processor, it is said to be operating in the stand-alone
mode. Conversely, if two or more AIC12s are daisy-linked and communicating with a single host
serial port, the AIC12 codecs are said to operate in the cascade mode. Up to 16 AIC12 codecs
can be cascaded. They can all be slave devices, but only one of them can be a master device.
This report mainly discusses the AIC12/DSP interface for codecs in the two-codec cascade
mode. The stand-alone slave operation is addressed in reference [5].
Whereas this report focuses on the two-device AIC12 cascade configuration, single-master and
single-slave, it touches lightly on the operation and configuration of the stand-alone master
configuration. The hardware configuration and software needed for this mode is quite straight
forward, once the user understands the operation of the master-slave cascade mode.
2HardwareSystem
The hardware and basic digital interface issues of the AIC/DSP system are addressed for the
AIC12 stand-alone master and two-device cascade mode.
2.1 Basic Stand-Alone Master Codec/DSP Interface
Figure 1 illustrates the typical digital interface when the AIC12 codec/C54xx™ DSP system
works in the codec’s stand-alone master mode.
'C54xxDSP
McBSP
BCLKR
BCLKX
BFSR
BFSX
BDR
BDX
CLKOUT
'AIC12 CODEC
DIN
DOUT
FS
SCLK
SMARTDM Port
SCL
SDA
Host Port
MCLK
FSD
M/S
RESET
PWRDN
DVDD
DVSS
IOVDD
IOVSS
Digital
Analog
Other Clock Source
IOVDD
{
I2C master
or S2C
10K
10K10K
IOVDD
10K
0.01uF 0.1uF 1uF
0.01uF 0.1uF 1uF
1.8VDC
3.3VDC
Digital Ground
Digital Ground
Reset Command
Power Down Command
10K
Figure 1. Typical AIC12/C54xx™ DSP Digital Interface, Stand-Alone Master Operation