Owner manual

14 DS245F4
CS8420
4. DATA I/O FLOW AND CLOCKING OPTIONS
The CS8420 can be configured for nine connectivity alternatives, referred to as data flows. Each data flow has an
associated clocking set-up. Figure 6 shows the data flow switching, along with the control register bits which control
the switches. This drawing only shows the audio data paths for simplicity. Figure 7 shows the internal clock routing
and the associated control register bits. The clock routing constraints determine which data routing options are ac-
tually usable.
Serial
Audio
Input
AES3
Encoder
Serial
Audio
Output
Receiver
Sample
Rate
Converter
RXP
RXN
ILRCK
ISCLK
SDIN
OLRCK
OSCLK
SDOU
T
TXP
TXN
AES3
TXOFFAESBP
SPD1-0
TXD1-0
SRCD
Figure 6. Software Mode Audio Data Flow Switching Options
SIMS
PLL
TXP
TXN
SDOUT
OSCLK
OLRCK
OMCKRMCK
RXP
ILRCK
ISCLK
SDIN
MUX
MUX
MUX
SWCLK
UNLOCK
01
0
1
01
CHANNEL
STATUS
MEMORY
USER
BIT
MEMORY
TRANSMIT
AES3
SERIAL
AUDIO
OUTPUT
INC
RXD0
MUX
0
1
OUTC
SERIAL
AUDIO
INPUT
RXD1
MUX
0
1
÷
CLK[1:0]
÷
RMCKF
SAMPLE
RATE
CONVERTER
Figure 7. CS8420 Clock Routing
*Note: When SWCLK mode is enabled, signal input on OMCK is only output through RMCK and not
routed back through the RXD1 multiplexer; RMCK is not bi-directional in this mode.