STTS2002_11 STMICROELECTRONICS [STMicroelectronics], STTS2002_11 Datasheet - Page 11

• Manufacturer Part Number: STTS2002_11
• Description: 2.3 V memory module temperature sensor with a 2 Kb SPD EEPROM
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

STTS2002
3
3.1
Note:
Temperature sensor operation
The temperature sensor continuously monitors the ambient temperature and updates the
temperature data register. Temperature data is latched internally by the device and may be
read by software from the bus host at any time.
The SMBus/I
same bus. This means that up to 8 memory modules can be supported, given that each
module has one such slave device address slot.
After initial power-on, the configuration registers are set to the default values. The software
can write to the configuration register to set bits per the bit definitions in
SMBus/I
For details of operation and usage of 2 Kb SPD EEPROM, refer to
EEPROM
SMBus/I
The registers in this device are selected by the pointer register. At power-up, the pointer
register is set to “00”, which is the capability register location. The pointer register latches
the last location it was set to. Each data register falls into one of three types of user
accessibility:
1.
2.
3.
A WRITE to this device will always include the address byte and the pointer byte. A WRITE
to any register other than the pointer register, requires two data bytes.
Reading this device is achieved in one of two ways:
●
●
The data byte transfers the MSB first. At the end of a READ, this device can accept either an
acknowledge (ACK) or no acknowledge (No ACK) status from the master. The No ACK
status is typically used as a signal for the slave that the master has read its last byte. This
device subsequently takes up to 125 ms to measure the temperature for the default
temperature resolution.
STTS2002 does not initiate clock stretching which is an optional I
Read-only
Write-only, and
WRITE/READ same address
If the location latched in the pointer register is correct (most of the time it is expected
that the pointer register will point to one of the read temperature registers because that
will be the data most frequently read), then the READ can simply consist of an address
byte, followed by retrieval of the two data bytes.
If the pointer register needs to be set, then an address byte, pointer byte, repeat start,
and another address byte will accomplish a READ.
2
C
operation.
communications.
2
2
C communications
C slave address selection pins allow up to 8 such devices to co-exist on the
Doc ID 15389 Rev 5
Temperature sensor operation
2
C bus feature.
Section 5: SPD
Section 3.1:
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