User manual

37 TREK-668/303 User Manual
Chapter 6 Setup
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 6.9.
Figure 6.9 RTC test - 5
6.3 Vehicle Power Management
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, an ignition signal is often used to turn
on or shutdown the system. When the system is in an OFF state and ignition is
turn ON, the VPM controller will countdown ON_DELAY; once it counts to zero,
the system will be turned on.
 Shutdown the system by ignition
When the system is powered on and the ignition is turn off, the
OFF_EVENT_DELAY will start to count down. During this stage, if the ignition is
back to ON, the VPM controller will stop countdown and reset the
OFF_EVENT_DELAY value. If OFF_EVENT_DELAY counts to zero, the VPM
controller will send an event (power button press) to the system and start to
count HARD_OFF_DELAY. Application programs could watch this event to do
pre-defined tasks, like storing data and preparing to turn off the system.
Once going into the 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.