Cirrus Logic AN312 - Manual (Page 12)

12 AN312REV2
AN312
4. USING 0x10 MODE WITH CS1810XX, CS4961XX OR CM-2
0x10 Mode is used when the designer wishes to synchronize the CobraNet clocks with an externally supplied word
clock (FS1). This is not possible with CM-2 and Silicon-based designs. The best that can be achieved is to use the
circuitry below to ensure that the audio clocks of the CobraNet interface are in phase with the audio clocks of the
existing circuit. In this case, the master clock is derived from the CobraNet device by using the circuitry shown in
Figure 20 , with the interface set to operate in clock mode 0x00. Any clocks required by the design can be taken from
the loadable counter taps, and these clocks will be in phase with the audio clocks (FS1 and SCLK) generated by the
CobraNet device. The Data In load value can be adjusted to ensure phase alignment if necessary.
Figure 20. 0x10 Mode Circuitry for Use with CM-2, CS1810xx or CS4961xx
5. REFERENCES
1. CobraNet Programmer's Reference Manual, http://www.cirrus.com
2. CobraNet Hardware User's Manual, http://www.cirrus.com
Loadable Counter
24.576 MHz
SCLK
MCLK_OUT Clock In
FS1
FS1
CobraNet Interface
D Flop
Q D
D Flop
Q D
AND
Load
Data In = 0x002
Clock In Clock In