CS8416-IZ CIRRUS [Cirrus Logic], CS8416-IZ Datasheet - Page 20

• Manufacturer Part Number: CS8416-IZ
• Description: 192 kHZ DIGITAL AUDIO INTERFACE RECEIVER
• Manufacturer: CIRRUS [Cirrus Logic]

6 CONTROL PORT DESCRIPTION
The control port is used to access the registers, al-
lowing the CS8416 to be configured for the desired
operational modes and formats. In addition, Chan-
nel Status and User data may be read through the
control port. The operation of the control port may
be completely asynchronous with respect to the au-
dio sample rates. However, to avoid potential inter-
ference problems, the control port pins should
remain static if no operation is required.
The control port has 2 modes: SPI and I
CS8416 acting as a slave device in both modes. SPI
mode is selected if there is a high to low transition
on the AD0/CS pin, after the RST pin has been
brought high. I
the AD0/CS pin to VL+ or DGND, thereby perma-
nently selecting the desired AD0 bit address state.
6.1
In SPI mode, CS is the CS8416 chip select signal,
CCLK is the control port bit clock (input into the
CS8416 from the microcontroller), CDIN is the in-
put data line from the microcontroller, CDOUT is
the output data line to the microcontroller. Data is
clocked in on the rising edge of CCLK and out on
the falling edge.
20
C C L K
CS
C D IN
C D O U T
AND TIMING
SPI Mode
ADDRESS
MAP = Memory Address Pointer, 8 bits, MSB first
0010000
C H IP
2
C mode is selected by connecting
High Impedance
R/W
M A P
Figure 11. Control Port Timing In SPI Mode
MSB
b y te 1
2
C, with the
DATA
b y te n
LSB
Figure 11
SPI mode. To write to a register, bring CS low. The
first seven bits on CDIN form the chip address and
must be 0010000. The eighth bit is a read/write in-
dicator (R/W), which should be low to write. The
next eight bits form the Memory Address Pointer
(MAP), which is set to the address of the register
that is to be updated. The next eight bits are the data
which will be placed into the register designated by
the MAP. During writes, the CDOUT output stays
in the Hi-Z state. It may be externally pulled high
or low with a 47 KΩ resistor, if desired.
There is a MAP auto increment capability, enabled
by the INCR bit in the MAP register. If INCR is a
zero, the MAP will stay constant for successive
read or writes. If INCR is set to a 1, the MAP will
auto increment after each byte is read or written, al-
lowing block reads or writes of successive regis-
ters. In the autoincrement mode, the MAP is
incremented in a linear fashion. Allowance must be
made for unused registers.
To read a register, the MAP has to be set to the cor-
rect address by executing a partial write cycle
which finishes (CS high) immediately after the
MAP byte. The MAP auto increment bit (INCR)
may be set or not, as desired. To begin a read, bring
CS low, send out the chip address and set the
A D D R E S S
C H IP
0010000
shows the operation of the control port in
R/W
MSB
LSB MSB
CS8416
DS578PP2
LSB