1°C Dual SMBus Sensor with Resistance Error Correction
Datasheet
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 below:
Table 3.4 SMBus Receive Byte Protocol
FIELD:
Bits:
START
1
SLAVE ADDR
7
RD
1
ACK
1
REG. DATA
8
NACK
1
STOP
1
3.5
Alert Response Address
The
ALERT
/
THERM2
output can be used as an SMBALERT# as described in
The Alert Response Address is polled by the Host whenever it detects an SMBALERT#, i.e. when the
ALERT
/
THERM2
pin is asserted. The EMC1002 will acknowledge the Alert Response Address and
respond with its device address as shown below:
Table 3.5 Modified SMBus Receive Byte Protocol Response to ARA
ALERT
RESPONSE
ADDRESS
7
EMC1002 SLAVE
ADDRESS
8
FIELD:
Bits:
START
1
RD
1
ACK
1
NACK
1
STOP
1
3.6
SMBus Addresses
The EMC1002-2 may be configured to one of four 7-bit slave addresses that are enabled based on
the pull-up resistor on the
ADDR
/
THERM
pin. The value of this pull-up resistor determines the slave
address per
Attempting to communicate with the
EMC1002 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 EMC1002 supports stretching of the SMCLK
signal by other devices on the SMBus but will not perform this operation itself. The EMC1002 has an
SMBus timeout feature. Bit 7 of the Consecutive Alert register enables this function when set to 1 (the
default setting is 0). When this feature is enabled, the SMBus will timeout after approximately 25ms
of inactivity.
Revision 1.1 (12-02-04)
PRELIMINARY DATASHEET
8
SMSC EMC1002
SMSC [ SMSC CORPORATION ]
