EKF PC7-FESTIVAL, User Manual

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User Guide • PC7-FESTIVAL • CompactPCI® PlusIO CPU Board
Hardware Monitor NCT7491
Attached to the SMBus, the PC7-FESTIVAL is provided with the hardware monitor NCT7491. This
device is capable to observe the temperatures of the board, processor cores, and on-board
memory, as well as several supply voltage rails with a resolution of 10 bit. The following table
shows the mapping of the voltage inputs of the NCT7491 to the corresponding supply voltages
of the PC7-FESTIVAL:
Input Source Resolution Register
(MSB/LSB)
VCCP Processor Core Voltage 2.93mV 0x21/0x76[3:2]
VTT +1.0V 2.20mV 0x1E/0x1F[5:4]
+2.5V/THERM# +1.2V 3.26mV 0x20/0x76[1:0]
VCC +3.3V 4.29mV 0x22/0x76[5:4]
+5Vin +5.0V 6.54mV 0x23/0x76[7:6]
+12Vin +12.0V 15.92mV 0x24/0x77[1:0]
PECI Core #0 absolute Temperature 1°C 0x04
PECI Core #1 absolute Temperature 1°C 0x05
PECI Core #2 absolute Temperature 1°C 0x06
PECI Core #3 absolute Temperature 1°C 0x07
D1+/D1- Memory Down absolute Temperature 0.25°C 0x25/0x77[3:2]
Local TEMP PC7 Surface Temperature 0.25°C 0x26/0x77[5:4]
Beside the continuous measuring of temperatures and voltages the NCT7491 may compare these
values against programmable upper and lower boundaries. As soon as a measurement violates
the allowed value range, the NCT7491 can request an over-temperature event on GPP_D1 input
of the CM238 or an interrupt via the GPP_D2 input (which may result in a system management
interrupt).
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