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TCS3471 Datasheet, PDF (11/23 Pages) TEXAS ADVANCED OPTOELECTRONIC SOLUTIONS – COLOR LIGHT-TO-DIGITAL CONVERTER
TCS3471
COLOR LIGHT-TO-DIGITAL CONVERTER
TAOS115 − MARCH 2011
I2C Protocol
Interface and control are accomplished through an I2C serial compatible interface (standard or fast mode) to
a set of registers that provide access to device control functions and output data. The devices support the 7-bit
I2C addressing protocol.
The I2C standard provides for three types of bus transaction: read, write, and a combined protocol (Figure 10).
During a write operation, the first byte written is a command byte followed by data. In a combined protocol, the
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N
P
R
S
Sr
W
...
1
S
first byte written is the command byte followed by reading a series of bytes. If a read command is issued, the
register address from the previous command will be used for data access. Likewise, if the MSB of the command
is not set, the device will write a series of bytes at the address stored in the last valid command with a register
lid address. The command byte contains either control information or a 5-bit register address. The control
commands can also be used to clear interrupts.
The I2C bus protocol was developed by Philips (now NXP). For a complete description of the I2C protocol, please
a review the NXP I2C design specification at http://www.i2c−bus.org/references/.
v Acknowledge (0)
Not Acknowledged (1)
ill Stop Condition
Read (1)
Start Condition
Repeated Start Condition
t Write (0)
Continuation of protocol
G s Master-to-Slave
Slave-to-Master
A t 1
7
s en S Slave Address
11
WA
8
1
Command Code A
I2C Write Protocol
8
Data Byte
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1
A ... P
am nt 1
7
co S Slave Address
11
RA
8
Data
1
8
A
Data
I2C Read Protocol
l 7
a Slave Address
11
WA
8
Command Code
11
A Sr
7
Slave Address
11
RA
ic 8
1
Data
A
nI2C Read Protocol — Combined Format
Tech Figure 10. I2C Protocols
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1
A ... P
8
1
1
Data
A ... P
Copyright E 2011, TAOS Inc.
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www.taosinc.com
The LUMENOLOGY r Company
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