ADLINK aTCA-6155 - Manual (Page 52)

38 Hardware Platform Management
4.2.5 Get Sensor Reading Command
Byte Data field
Request
data
1 Sensor Number (FFh = reserved)
Response
data
1 Completion Code
2
Sensor reading
Byte 1: byte of reading. Ignore on read if sensor does not return an
numeric (analog) reading.
3
[7] - 0b = All Event Messages disabled from this sensor
[6] - 0b = sensor scanning disabled
[5] - 1b = reading/state unavailable (formerly “initial update in
progress”).
This bit is set to indicate that a ‘re-arm’ or ‘Set Event Receiver’
command has been used to request an update of the sensor
status, and that update has not occurred yet. Software should use
this bit to avoid getting an incorrect status while the first sensor
update is in progress. This bit is only required if it is possible for
the controller to receive and process a ‘Get Sensor Reading’ or
‘Get Sensor Event Status’ command for the sensor before the
update has completed. This is most likely to be the case for
sensors, such as fan RPM sensors, that may require seconds to
accumulate the first reading after a re-arm. The bit is also used to
indicate when a reading/state is unavailable because the
management controller cannot obtain a valid reading or state for
the monitored entity, typically because the entity is not present.
See PICMG Specification 3.0, Section 16.4, Event Status, Event
Conditions, and Present State and Section 16.6, Re-arming for
more information.
[4:0] - reserved. Ignore on read.