Cirrus Logic AN312 - Manual (Page 11)

AN312REV2 11
AN312
3.1.6 0x14 Mode for CM-2/CS1810xx/CS4961xx-Based Devices
Note: The 0x14 clock mode only works with devices running Rev. 2.11.6 firmware or later.
Mode 0x14 for CM-2 and CobraNet chips is primarily intended to allow complete audio clock slaving of
one or more CobraNet devices to a master CobraNet device within the same chassis.
MCLK, SCLK, and FS1 are all supplied to the slave device by the master device. External divide by 2 logic
must also be used on DAI1_SCLK when using 16x16 channel chips.
Changing to this mode dynamically has not proven to work well consistently. The CNCustom firmware
modification program should be used to create slave device firmware with the Conductor and Performer
clock modes set to values of 0x14 so that the slave device(s) will boot up in mode 0x14. The hardware
should be designed so that the slave device(s) will always be supplied by all required clocks and will al-
ways operate in mode 0x14. The internal clock circuitry for the master device will be as that shown and
described elsewhere in this document for the master clock mode in use. A description of the internal clock
circuitry is not applicable for the slave device(s) as all clocks are supplied to them directly.
Figure 18. Clock Circuit as Used by Mode 0x14 with CM-2 or Chips with 2x2 or 8x8 Audio Channels
Figure 19. Clock Circuit as Used by Mode 0x14 with CM-2 or Chips with 16x16 Audio Channels
3.072 / 6.144 MHz
24.576 MHz
MCLK_IN (8)
DAI1_LRCLK (138)
48 / 96 kHz
MCLK_IN (8)
DAI1_SCLK (137)
CobraNet Interface
(Slave)
Mode 0x14
CobraNet Interface
(Master)
(Typically Mode 0)
DAO1_SCLK (20)
DAO1_LRCLK (22)
DAO1_SCLK (20)
VCXO
DAI1_SCLK (137)
DAI1_LRCLK (138)
DAO1_LRCLK (22)
6.144 MHz
24.576 MHz MCLK_IN (8)
DAI1_LRCLK (138)
96 kHz
MCLK_IN (8)
DAI1_SCLK (137)
CobraNet Interface
(Slave)
Mode 0x14
CobraNet Interface
(Master)
(Typically Mode 0)
DAO1_SCLK (20)
DAO1_LRCLK (22)
DAO1_SCLK (20)
VCXO
DAI1_SCLK (137)
DAI1_LRCLK (138)
DAO1_LRCLK (22)
DAO2_SCLK (12) /2 3.072 MHz
48 kHz DAO2_LRCLK (14) DAO2_LRCLK (14)