FIC A360 - Manual (Page 87)

Software Functional Overview
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FIC A360 Service Manual
1. The OS notifies the hardware of the new cooling mode by running the Set
Cooling Policy (_SCP) control method.
2. When the hardware receives the notification, it can set a new temperature
for both cooling policies and notify the OS that the thermal zone policy
temperatures have changed.
3. The OS re-evaluates _PSV and _ACx.
Resetting Cooling Temperatures to Adjust to Bay Device Insertion or
Removal
The hardware can adjust the thermal zone temperature to accommodate the
maximum operating temperature of a bay device as necessary. For example,
1. Hardware detects that a device was inserted into or removed from the bay
and resets the _PSV and/or _ACx and then notifies the OS of the thermal
and device insertion events.
2. The OS reenumerates the devices and reevaluates _PSV and _ACx.
Resetting Cooling Temperatures to Implement Hysteresis
An OEM can build hysteresis into platform thermal design by dynamically
resetting cooling temperatures. For example,
1. When the heat increases to the temperature designated by _ACx, the OS
will turn on the associated active cooling device and the hardware will
reset the ACx value to a lower temperature.
2. The hardware will then run the Notify command and the OS will
reevaluate the new temperatures. Because of the lower _ACx value now,
the fan will be turned off at a lower temperature than when turned on
.
3. When the temperature hits the lower _ACx value, the OS will turn off the
fan and reevaluate the control methods when notified.