Datasheet

Functional Description
162 Intel® Xeon® Processor D-1500 Product Family
Datasheet - Volume 1 of 4: Integrated Platform Controller Hub
March 2015
• Writes are not allowed to this address, and result in indeterminate behavior.
• Packet Error Code (PEC) may be enabled or not, which is set up by BIOS.
3.21.3.2 Block Read Command
The external controller may read thermal information from Intel® Xeon® Processor D-
1500 Product Family using the SMBus Block Read Command. Byte-read and Word-read
SMBus commands are not supported. The reads use a different address than the
writes.
The command format follows the Block Read format of the SMBus specification.
Intel® Xeon® Processor D-1500 Product Family returns a single byte of data,
indicating the temperature between 0 °C (0x00) and 254 °C (0xFE). A read of 0xFF
indicates that the sensor is not yet enabled. For more information, see
Section 3.21.3.3.1.
3.21.3.3 Read Data Format
For each of the data fields an ERROR Code is listed below. This code indicates that
Intel® Xeon® Processor D-1500 Product Family failed in its access to the device. This
would be for the case where the read returned no data, or some illegal value. In
general that would mean the device is broken. The EC can treat the device that failed
the read as broken or with some fail-safe mechanism.
3.21.3.3.1 Intel® Xeon® Processor D-1500 Product Family Temperature
The temperature readings for Intel® Xeon® Processor D-1500 Product Family are 8-bit
unsigned values from 0–255. The minimum granularity supported by the internal
thermal sensor is 1 °C. Thus, there are no fractional values for Intel® Xeon® Processor
D-1500 Product Family temperatures. The device returns a temperature between 0 °C
(0x00) and 254 °C (0xFE). Devices that are not yet enabled return the
value 0xFF.
Note: Sensors used within the components do not support values below 0°C, so this field is
treated as 8 bits (0-255) absolute.
3.21.3.4 Thermal Data Update Rate
The temperature values are updated every 1 ms in Intel® Xeon® Processor D-1500
Product Family, so reading more often than that simply returns the same data multiple
times. Also, the data may be up to 1 ms old if the external controller reads the data
right before the next update window.
3.21.3.5 Temperature Comparator and Alert
Intel® Xeon® Processor D-1500 Product Family has the ability to alert the external
controller when temperatures are out of range. This is done using Intel® Xeon®
Processor D-1500 Product Family TEMP_ALERT# signal. The alert is a simple
comparator. If any device's temperature is outside the limit range for that device, then
the signal is asserted (electrical low). This alert does not use the SML1ALERT#.
Intel® Xeon® Processor D-1500 Product Family supports 2 ranges: an upper and lower
limit (8 bits each, in degrees C) for Intel® Xeon® Processor D-1500 Product Family
temperature.