Figure 6.14 Rtc Test-5 - Advantech TREK-550 User Manual

2. RTC Alarm Setting: You may also set Alarm time; you may wake up the
system by the time you have set. Please refer to below figure 6.
6.3 Vehicle
6.3.1 Power management Mechanism
The feature of Vehicle Power Management (VPM) is provided for users to
fulfill the special requirements on in-vehicle applications.

Ignition on/off

Turn on the system by ignition
For the cases of in-vehicle applications, ignition signal is often used to turn on or
shutdown system. When the system is in OFF state and ignition is turn ON, the VPM
controller will countdown ON_DELAY; once it counts to zero, the system will be turn on.

Shutdown the system by ignition
When the system is powered on and ignition is turn off, the OFF_EVENT_DELAY will start
to count down. During this stage, if the ignition is back to ON, VPM controller will stop
countdown and reset the OFF_EVENT_DELAY value. If OFF_EVENT_DELAY is keeping
counting to zero, VPM controller will send a event (power button press) to the system
and start to count HARD_OFF_DELAY. The application programs could watch this event to
do pre-defined tasks, like storing the data and preparing to turn off system.
Once going into HARD_OFF_DELAY stage, this process will be irreversible. And if
HARD_OFF_DELAY counts to zero, the system power will be cut off abruptly.

Low battery protection
To avoid draining out the car battery, low-battery protection is involved to ensure the
car battery is capable to start the vehicle. When the system is ON, VPM controller will
monitor the car battery voltage. If the battery voltage is lower than a programmable
TREK-550 User manual
Figure 6.14 RTC test -5
Power Management
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