EMC1046 Standard Microsystems Corp., EMC1046 Datasheet - Page 12

• Manufacturer Part Number: EMC1046
• Description: 1 Degree C Multiple Temperature Sensor With Beta Compensation And Hottest Of Thermal Zones
• Manufacturer: Standard Microsystems Corp.

Chapter 3 System Management Bus Interface Protocol
Revision 0.66 (06-02-08)
3.1
3.2
SMDATA
START
1 -> 0
SMCLK
System Management Bus Interface Protocol
Write Byte
The EMC1046/EMC1047 communicate with a host controller, such as an SMSC SIO, through the
SMBus. The SMBus is a two-wire serial communication protocol between a computer host and its
peripheral devices. A detailed timing diagram is shown in
The EMC1046/EMC1047 are SMBus 2.0 compatible and support Send Byte, Read Byte, Write Byte,
and Receive Byte, as valid protocols as shown below.
All of the below protocols use the convention in
Attempting to communicate with the EMC1046/EMC1047 SMBus interface with an invalid slave
address or invalid protocol will result in no response from the device and will not affect its register
contents. Stretching of the SMCLK signal is supported, provided other devices on the SMBus control
the timing.
The Write Byte is used to write one byte of data to the registers as shown below
ADDRESS
1001_100
P
SLAVE
T
BUF
S
T
T
S - Start Condition
HD:STA
LOW
WR
0
T
HD:DAT
T
RISE
Figure 3.1 SMBus Timing Diagram
DATA SENT
ACK
TO DEVICE
Table 3.2 Write Byte Protocol
0
Table 3.1 Protocol Format
T
HIGH
1°C Multiple Temperature Sensor with Beta Compensation and Hottest of Thermal Zones
DATASHEET
REGISTER
T
ADDRESS
SU:DAT
T
XXh
FALL
12
DATA SENT TO
THE HOST
Table
3.1.
ACK
0
Figure
S
T
T
SU:STA
HD:STA
3.1.
REGISTER
DATA
XXh
P - Stop Condition
SMSC EMC1046/EMC1047
Table
ACK
0
T
SU:STO
3.2:
Datasheet
0 -> 1
STOP
P