CS4360 Datasheet, PDF (25/36 Pages) Cirrus Logic – 24-Bit, 192 kHz 6 Channel D/A Converter

CS4360
SDA
001000
ADDR
AD0
R/W ACK
Note 1
DATA
1-8
ACK
DATA
1-8
ACK
SCL
Start
Stop
Note: If operation is a write, this byte contains the Memory Address Pointer, MAP.
Figure 5. Control Port Timing, Two-Wire Format
waiting for the CS4360 to acknowledge between
each byte. To end the transaction, send a STOP
condition.
7.3.2 Reading in Two-Wire Format
To communicate with the CS4360, initiate a
START condition of the bus. Next, send the chip
address. The eighth bit of the address byte is the
R/W bit (high for a read). The contents of the reg-
ister pointed to by the MAP will be output after the
chip address. To read multiple registers, continue
providing a clock and issue an ACK after each
byte. To end the transaction, send a STOP condi-
tion.
7.4 SPI Format
In SPI format, CS is the CS4360 chip select signal,
CCLK is the control port bit clock, CDIN is the in-
put data line from the microcontroller and the chip
address is 0010000. CS, CCLK and CDIN are all
inputs and data is clocked in on the rising edge of
CCLK.
Note that the CS4360 is write-only when in SPI
format.
7.4.1 Writing in SPI
Figure 6 shows the operation of the control port in
SPI format. To write to a register, bring CS low.
The first 7 bits on CDIN form the chip address and
must be 0010000. The eighth bit is a read/write in-
dicator (R/W), which must be low to write. The
next 8 bits form the Memory Address Pointer
(MAP), which is set to the address of the register
that is to be updated. The next 8 bits are the data
which will be placed into register designated by the
MAP. To write multiple registers, keep CS low and
continue providing clocks on CCLK. End the read
transaction by setting CS high.
CS
CCLK
CDIN
CHIP
ADDRESS
MAP
DATA
0010000
R/W
MSB
LSB
byte 1 byte n
MAP = Memory Address Pointer
Figure 6. Control Port Timing, SPI Format
DS517PP1
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