TC1322_05 Datasheet, PDF (7/16 Pages) Microchip Technology – 12-Bit Digital-to-Analog Converter with Two-Wire Interface

TC1322
FIGURE 3-1:
SMBus PROTOCOLS
Write 1-Byte Format
S
Address
R/W ACK Command
ACK Data ACK P
7-Bits
0
8-Bits
8-Bits
Slave Address
Write 2-Byte Format
Command Byte: selects
which register you are
writing to.
Data Byte: data goes
into the register set
by the command byte.
S
Address
R/W ACK Command
ACK Data ACK Data ACK P
7-Bits
0
8-Bits
8-Bits
8-Bits
Slave Address
Command Byte: selects
which register you are
writing to.
Data Byte: data goes
into the register set
by the command byte.
Read 1-Byte Format
S ^Address R/W ACK Command ACK S Address R/W ACK ^Data NACK P
7-Bits 0
8-Bits
7-Bits 1
8-Bits
Slave Address
Command Byte: selects Slave Address: repeated Data Byte: reads from
which register you are due to change in data the register set by the
reading from.
flow direction.
command byte.
Read 2-Byte Format
S Address R/W ACK Command ACK S Address R/W ACK Data ACK Data NACK P
7-Bits 0
8-Bits
7-Bits 1
8-Bits
8-Bits
Slave Address
Command Byte: selects Slave Address: repeated Data Byte: reads from
which register you are due to change in data the register set by the
reading from.
flow direction.
command byte.
Receive 1-Byte Format
S Address R/W ACK Data NACK P
7-Bits 1
8-Bits
S = START Condition
Data Byte: reads data from
P = STOP Condition
the register commanded by
Shaded = Slave Transmission the last read byte or write
byte transmission.
Receive 1-Byte Format
S Address R/W ACK Data ACK Data NACK P
7-Bits 1
8-Bits
8-Bits
S = START Condition
P = STOP Condition
Shaded = Slave Transmission
Data Byte: reads data from
the register commanded by
the last read byte or write
byte transmission.
© 2005 Microchip Technology Inc.
DS21388C-page 7