Intel SE7520JR2 5.3.2Power Control Sources, 5.3.3Power-upSequence, 5.3.4Power-downSequence, 5.3.5System Reset Control, 5.3.5.1Reset Signal Output

Platform Management Intel® Server Board SE7520JR2

5.3.2Power Control Sources

The sources listed in the following table can initiate power-up and/or power-down activity.

Table 47: Power Control Initiators

Source	External Signal Name or	Capabilities
	Internal Subsystem
Power button	Front control power button	Turns power on or off
mBMC Watchdog Timer	Internal mBMC timer	Turns power off or power cycle
Platform Event Filtering	PEF	Turns power off or power cycle
Command	Routed through command processor	Turns power on or off, or power cycle
Power state retention	Implemented via mBMC internal logic	Turns power on when AC power returns

5.3.3Power-up Sequence

When turning on the system power after one of the event occurrences, the mBMC executes the following procedure:

1.The mBMC asserts Power Supply (PS) Power On via the chipset and waits for the power subsystem to assert Power Good. The system is reset.

2.The mBMC initializes all sensors to their Power On initialization states. The Init Agent is run.

3.The mBMC attempts to boot the system by running the FRB algorithm, if FRB is enabled.

5.3.4Power-down Sequence

To power down the system, the mBMC effectively performs the sequence of power-up steps in reverse order. It occur as follows:

1.The mBMC asserts system reset.

2.The mBMC de-asserts the Power On signal via the chipset.

3.The power subsystem turns off system power upon de-assertion of the Power On signal.

5.3.5System Reset Control

5.3.5.1Reset Signal Output

The mBMC asserts the System Reset signal on the baseboard to perform a system reset. The mBMC asserts the System Reset signal before powering the system up. After power is stable as indicated by the power subsystem Power Good signal, the mBMC sets the processor enable state as appropriate and de-asserts the System Reset signal, taking the system out of reset. The system reset signal responds to the control panel or IPMI commands.

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