EMC1043_07 Datasheet, PDF (10/29 Pages) SMSC Corporation – 1C Triple Temperature Sensor with Beta Compensation and Hotter of Two Zones

2.3.3
1°C Triple Temperature Sensor with Beta Compensation and Hotter of Two Zones
Send Byte
Datasheet
The Send Byte protocol is used to set the Internal Address Register to the correct Address as shown
in Table 2.5. The Send Byte can be followed by the Receive Byte protocol described in Table 2.6 to
read data from the register. The send byte protocol cannot be used to write data - if data is to be
written to a register then the write byte protocol must be used as described in Section 2.3.1.
START
1
SLAVE ADDR
7
Table 2.5 Send Byte Protocol
WR
ACK
1
1
REG. ADDR
8
ACK
1
STOP
1
2.3.4
Receive Byte
The Receive Byte protocol is used to read data from a register when the internal register address
pointer is known to be at the right location (e.g. set via Send Byte). This can be used for consecutive
reads of the same register as shown in Table 2.6.
START
1
Table 2.6 Receive Byte Protocol
SLAVE ADDR
7
RD
ACK
1
1
REG. DATA
8
NACK
1
STOP
1
2.3.5
2.4
SMBus Timing Diagram
The Timing for the SMBus is shown in Figure 2.1.
SMBus Addresses
The EMC1043 may be ordered with one of four slave addresses as shown in ORDER Numbers:.
Attempting to communicate with the EMC1043 SMBus interface with an invalid slave address or invalid
protocol results in no response from the device and does not affect its register contents. The EMC1043
supports stretching of the SMCLK signal by other devices on the SMBus but will not perform this
operation itself.
2.5
SMBus Timeout
The EMC1043 includes an SMBus time-out feature. Following a 25 ms period of inactivity on the
SMBus, the device will time-out and reset the SMBus interface.
Revision 1.37 (02-05-07)
10
DATASHEET
SMSC EMC1043