Crystal CS4231A, Manual

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output clocks will stretch, but will not have any
glitches. This allows the serial port to operate
through a sample frequency change. The first format - SPF0, shown in Figure 6, is
called 64-bit enhanced. This format has 64
SCLKs per frame with a one bit period wide
FSYNC that precedes the frame. The first 16 bits
FSYNC
SCLK
SDOUT
15 14 13 12
...
16 Bits
Left Data
0 15 14
...
0
16 Bits
Right Data
8 zeros
SDIN
15 14 13 12
...
16 Bits
Left Data
0 15 14
...
0
16 Bits
Right Data
INT = Interrupt Bit
CEN = Capture Enable
PEN = Playback Enable
OVR = Left Overrange or
Right Overrange
INT
7 zeros
CEN PEN OVR
13 zeros
32 Bits
...
Figure 6. 64-bit enhanced mode (SF1,0 = 00)
FSYNC
Left Data
SCLK
SDOUT/
15 14 13 0
...
15 14 13 0
...
15
Right Data
16 Clocks 16 Clocks 16 Clocks 16 Clocks
SDIN
Figure 7. 64-bit mode (SF1,0 = 01)
SCLK
FSYNC
Left Data
SDOUT/
15 14 13 0
...
16 Clocks
15 14 13 0
...
16 Clocks
15
Right Data
32 No-Clock bit periods
...
Left Data
14
...
...
SDIN
Figure 8. 32-bit mode (SF1,0 = 10)
CS4231A
DS139PP2 17