DART-6UL suspend: Difference between revisions
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To suspend to RAM: | To suspend to RAM: | ||
<pre> | <pre> | ||
Enable Wi-Fi if not enabled to ensure the firmware is loaded: | |||
# ifconfig wlan0 up | |||
Disable Wi-Fi to put it into sleep state: | |||
# ifconfig wlan0 down | |||
Disable Bluetooth | |||
# echo 0 > /sys/class/gpio/gpio132/value | |||
Enter Sleep mode | |||
# pm-suspend | # pm-suspend | ||
</pre> | </pre> |
Revision as of 11:09, 6 May 2020
Suspend to RAM
Suspend to RAM
This state offers significant power savings as everything in the system is put into a low-power state, except for memory, which is placed into the self-refresh mode to retain its contents.
NOTE:
The test in this section was performed with LCD display disconnected.
The test in this section was performed with LCD display disconnected.
To suspend to RAM:
Enable Wi-Fi if not enabled to ensure the firmware is loaded: # ifconfig wlan0 up Disable Wi-Fi to put it into sleep state: # ifconfig wlan0 down Disable Bluetooth # echo 0 > /sys/class/gpio/gpio132/value Enter Sleep mode # pm-suspend
Wake up
There are many possible ways to wake up from suspend.
A few examples:
- Pushing the ON/OFF button (when present on the board)
- Pushing a button on the board which has the boolean property "gpio-key,wakeup" set in its device tree node (under gpio_keys), e.g.:
gpio-keys { compatible = "gpio-keys"; pinctrl-names = "default"; pinctrl-0 = <&pinctrl_gpio_keys>; back { label = "Back"; gpios = <&gpio5 20 GPIO_ACTIVE_LOW>; linux,code = <KEY_BACK>; gpio-key,wakeup; }; };
Current consumption when suspended
To measure the current remove resistor R4 on the 6ULCustomBoard and connect an ammeter instead.
The expected measured current consumption should be around 4.5mA at 3.3V