APM (Advanced Power Management) is a standard in power management developed by Intel and Microsoft, which allows the operating system to control the amount of power sent to devices. Select EMAC products allow for APM Sleep, a command that puts the device into a lower power "deep sleep" state and minimizes the device's power consumption.
From the command line, use command:
where hh is hours and mm is minutes, to suspend for hh:mm amount of time
Alternatively the + can be left off to specify a time when the device would awaken. "apmsleep 08:00" would suspend until 8am
After the given time, the device will resume normal operation and power consumption.
The SoM-iMX6U was designed with APM Sleep in mind, and when issued the command, the SoM-iMX6U current drops from typical current of 160mA to minimal current of 3.5mA.
APM Sleep also sends specified signals to the carrier board to disable systems to further save power. SoM-IMX6U Product site
The DEV-IOT6U Development Kit (SoM-112ES Carrier Board + SoM-iMX6U) runs at a typical current of 390mA. When APM Sleep is activated, the kit can reach to a minimal current draw of 70.5mA. In this kit the SoM-iMX6U typically runs at 194mA and drops to 5.2mA in APM Sleep. Some boards do not allow for some of the features to be toggled off, which is why this is the lowest power state for the DEV-IOT6U.