Datasheet

SRC4192, SRC4193
SBFS022B
27
www.ti.com
The frame rate is equal to the output sampling frequency, f
s
.
The BCKO frequency for the TDM interface is N*64f
s
, where
N is the number of devices included in the daisy chain. For
Master mode, the output BCKO frequency is fixed to the
reference clock (RCKI) input frequency. The number of
devices that can be daisy-chained in TDM mode is depen-
dent upon the output sampling frequency and the BCKO
frequency, leading to the following numerical relationship:
Number of Daisy-Chained Devices = (f
BCKO
/ f
s
) / 64
Where:
f
BCKO
= Output Port Bit Clock (BCKO), 27.648 MHz maximum
f
s
= Output Port Sampling (or LRCKO) Frequency, 216kHz
maximum.
This relationship holds true for both Slave and Master modes.
TDMI
SRC4192, SRC4193
Slave #N
SDOUT
LRCKO
BCKO
RCKI
TDMI
SRC4192, SRC4193
Slave #2
SDOUT
LRCKO
BCKO
RCKI
TDMI
SRC4192, SRC4193
Slave #1
SDOUT
LRCKO
BCKO
RCKI
DRn
FSRn
CLKRn
CLKIN or CLKSn
TMS320C671x
McBSP
Clock
Generator
n = 0 or 1
TDMI
SRC4192, SRC4193
Master
SDOUT
LRCKO
BCKO
RCKI
TDMI
SRC4192, SRC4193
Slave #2
SDOUT
LRCKO
BCKO
RCKI
TDMI
SRC4192, SRC4193
Slave #1
SDOUT
LRCKO
BCKO
RCKI
DRn
FSRn
CLKRn
CLKIN or CLKSn
TMS320C671x
McBSP
Clock
Generator
n = 0 or 1
Figures 16 and 17 show typical connection schemes for TDM
mode. Although the TMS320C671x DSP family is shown as
the audio processing engine in these figures, other TI digital
signal processors with a multi-channel buffered serial port
(McBSP
TM
) may also function with this arrangement. Inter-
facing to processors from other manufacturers is also pos-
sible. Refer to Figure 7 in this data sheet, along with the
equivalent serial port timing diagrams shown in the DSP data
sheet, to determine compatibility.
FIGURE 16. TDM Interface where all Devices are Slaves.
FIGURE 17. TDM Interface where one Device is Master to Multiple Slaves.