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9.
View/change other settings...
Choosing this option will display a sub menu and allows you to set these parameters:
Default state when powered
It is “OFF” by default, which means your Raspberry Pi will not be turned on when power
supply is connected to Witty Pi 3, and you will need to tap the button on Witty Pi 3 to start it.
Here you can set it to 1 (ON) or 0 (OFF).
Power cut delay after shutdown
Default value is 5.0 seconds, which means Witty Pi 3 will fully cut the power after 5 seconds
since Raspberry Pi has been shut down. Here you can input a number between 0.0 to 8.0.
Pulsing interval during sleep
This parameter will decide how long Witty Pi 3’s micro control will wake up and drive the
white LED and/or the dummy load. By default, this interval is 4 seconds. If you wish the
white LED blinks slower, or the dummy load draws current less frequently, you can choose a
bigger value. Here you can only pick a value from 1, 2, 4 and 8.
White LED duration
This parameter will decide how long the white LED should stay on, when Witty Pi 3 blinks it
during the sleep. The default value is 100, and you can use bigger value if you wish the white
LED to stay on for longer. Here you can input number from 0 to 255. If you input 0, the white
LED will not blink at all.
Dummy load duration
This parameter will decide how long the dummy load should draw current from the power
source.
What is (pulsing) dummy load? It is a trick to keep power bank alive, when Raspberry Pi is
off. If you are using power bank to power Witty Pi 3 + Raspberry Pi, after turning off
Raspberry Pi and cut the power, Witty Pi 3 only draws about 1mA from the power bank,
which is way too small to keep the power bank alive. If the power bank goes to sleep mode, it
will not provide any power to Witty Pi 3 and hence your Raspberry Pi will not wake up when
scheduled startup is due. Pulsing dummy load is such a trick, that it draws rather big current
from the power bank for a short duration and it does so with a fixed interval. That way the
power bank might be fooled and think the load is heavy enough, and avoid entering the sleep
mode.
The default value of dummy load duration is 0, which means disabled (no dummy load at all).
You can set a value between 0 and 255 here. However,
we suggest to use smallest value
that could keep your power bank alive, usually 10 will do
.
Vin adjustment
The voltage is measured by the 10-bit ADC in micro controller. Due to the inaccuracy of
internal voltage standard and error on divider resistors, the result could have up to 5% error.