Technical Description
miriac MPX-LX2160A User Manual
V1.4
15/73
© MicroSys Electronics GmbH 2020
4.4
Management Engine (ME)
The management engine is handled by a Renesas S128 microcontroller
R7FS128783A01CFM.
The microcontroller (µC) is responsible for power sequencing and supervision,
configuration of on-board supplies, voltage monitoring and safety as well as
security aspects.
The micro
controller’s firmware can be modified for customer specific applications
on request.
4.4.1
System Startup
On application of an input voltage, the µC is the first component to start (once VIN
>= 3.0V). The uC runs the initialization and setup for
•
Clock Generator
•
Temperature Sensor Limits
•
Fan Controller
•
Checking programmed values of Power Switches for VDD and VDDQ
After a successful setup and check, the uC will start the Power Sequencer which
monitors all Power Rails. Next, the VDD and VDDQ are ramped up, so that the
SoC is powered. Finally, the CPLD is instructed to select the RCW source and
release the PowerOn Reset to the SoC.
The complete System Startup Sequence takes around 240msec.
4.4.2
System Monitoring
The ME is one part of the complex System Monitoring. Others are
•
Power Switches for VDD and VDDQ are monitoring their own voltages.
•
Power Sequencer checks voltages are in range (see 4.6.1).
•
Temperature Sensors are monitoring temperatures against set limits.
The components are all able to shut down the system on their own. The ME
collects all information for 'black box recording' of emergency shutdowns.
The SoC fan speed is determined by SoC temperature readings.
All the different voltage, fan and temperature sensors are read by the ME in a
cyclic loop. By setting lower limits than those used for a hard shutdown, the ME
can react earlier to potential problems and inform the SoC thus allowing it to take
evasive action.
