MAX9853 Maxim Integrated Products, MAX9853 Datasheet - Page 63

• Manufacturer Part Number: MAX9853
• Description: (MAX9851 / MAX9853) Stereo Audio CODECs
• Manufacturer: Maxim Integrated Products

Send the slave address with the R/W bit set to 1 to initi-
ate a read operation. The MAX9851/MAX9853 acknowl-
edge receipt of its slave address by pulling SDA low
during the ninth SCL clock pulse. A START command
followed by a read command resets the address pointer
to register 0x00. The first byte transmitted from the
MAX9851/MAX9853 will be the contents of register 0x00.
Transmitted data is valid on the rising edge of the mas-
ter-generated serial clock (SCL). The address pointer
autoincrements after each read data byte. This autoin-
crement feature allows all registers to be read sequen-
tially within one continuous frame. A STOP condition can
be issued after any number of read data bytes. If a STOP
condition is issued followed by another read operation,
the first data byte to be read will be from register 0x00
and subsequent reads will autoincrement the address
pointer until the next STOP condition. The address point-
er can be preset to a specific register before a read
Figure 15. Reading One Indexed Byte of Data from the MAX9851/MAX9853
Figure 16. Reading n-Bytes of Indexed Data from the MAX9851/MAX9853
Stereo Audio CODECs with Microphone, DirectDrive
S
ACKNOWLEDGE FROM MAX9851/
S
Headphones, Speaker Amplifiers, or Line Outputs
SLAVE ADDRESS
ACKNOWLEDGE FROM MAX9851/
SLAVE ADDRESS
______________________________________________________________________________________
MAX9853
R/W
MAX9853
R/W
0
A
0
ACKNOWLEDGE FROM MAX9851/
A
ACKNOWLEDGE FROM MAX9851/
REGISTER ADDRESS
Read Data Format
REGISTER ADDRESS
REPEATED START
MAX9853
REPEATED START
MAX9853
A
Sr
A
ACKNOWLEDGE FROM MAX9851/
Sr
ACKNOWLEDGE FROM MAX9851/
SLAVE ADDRESS
command is issued. The master presets the address
pointer by first sending the MAX9851/MAX9853’s slave
address with the R/W bit set to 0 followed by the register
address. A REPEATED START condition is then sent fol-
lowed by the slave address with the R/W bit set to 1. The
MAX9851/MAX9853 transmit the contents of the speci-
fied register. The address pointer auto-increments after
transmitting the first byte. Attempting to read from regis-
ter addresses higher than 0x1F results in repeated reads
of 0x1F. Note that 0x1C to 0x1F are reserved registers.
The master acknowledges receipt of each read byte dur-
ing the acknowledge clock pulse. The master must
acknowledge all correctly received bytes except the last
byte. The final byte must be followed by a not acknowl-
edge from the master and then a STOP condition. Figure
15 illustrates the frame format for reading one byte from
the MAX9851/MAX9853. Figure 16 illustrates the frame
format for reading multiple bytes from the MAX9851/
MAX9853.
SLAVE ADDRESS
MAX9853
MAX9853
R/W
R/W
1
A
1
NOT ACKNOWLEDGE FROM MASTER
A
DATA BYTE
1 BYTE
REGISTER ADDRESS POINTER
AUTO-INCREMENT INTERNAL
DATA BYTE
1 BYTE
REGISTER ADDRESS POINTER
AUTO-INCREMENT INTERNAL
A
P
A
63