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86 CPCI-7806/CPCI-7806RC Pentium/Celeron M Universal CompactPCI Single Board Computer
Publication No. 500-657806-000 Rev. G
The IPMI subsystem contains several sensors. They provide the voltages and
temperature reading of the system. The various sensor settings like threshold,
hysteresis, event enable, etc., are statically configured in the Sensor Data Records.
The sensor readings returned are in their “raw” values; to convert them to actual
values use the following formulas below.
a. For 3.3 V sensors
V
a
= (V
r
/ 256) * (3.3 / 2.5) * 3.3
Where V
a
= actual voltage
V
r
= “raw” sensor reading
e.g.: if sensor 0x41 says 0xC0 (192 decimal), the actual voltage is
(192/256) * 3.3/2.5 * 3.3 = 3.267 V.
Table E-11 NetFn 0x04, Cmd 0x2D
Byte
Value
Data Field
Comments
Request-data
1
XXh
Sensor Number (FFh reserved)
Response-data 1
00h
Completion code
2
XXh
Sensor reading
3
XXh
[7] - 0b = All event messages disabled
for this sensor
[6] - 0b = Sensor scanning disabled
[5] - 1b = Initial update in progress.
[4-0] - reserved
4
XXh
For threshold-based sensors,
Present threshold comparison status.
For discrete reading sensors,
State 0-7 assert condition.
5
XXh
State 8-14 assert condition
Optional for discrete reading
sensors
Sensor No
Type
Comments
0x41
3.3V
Switched on/off by hotswap
controller, *BDSEL etc.
0x42
5V
Switched on/off by hotswap
controller, *BDSEL etc.
0x43
3.3V IN backplane
0x44
5V IN backplane
0x60
Temp Sensor
0x61
Temp Sensor