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Host Monitor X start signals

Overview⚓︎

There are 5 start signals on different connectors. Start 1 to 4 is meant to be used to start the device and Start 5 is meant to be used with an external LED or an output for signal start. Only one external start signal is needed to start the device. They are all connected to a a singel input and it can be read from gpio-key event or unbind gpio-key to use this signal and other digital in signals as regular gpios.

Note unbind gpio-keys will lose the wake-up possibility on those signals and all digital in signals.

To start the device the current signal time needs to be at least 2-3 seconds long (in the future we might shorter the time) for the unit to start up and be able to hold the start signal internally.

The internal signal (called power_on) is also used to hold the power on even if the START 1,2,3 or 4 is down. If you want to use the the cut-off function, make sure that IN_START is low(0) before use poweroff or shutdown.

To shut down the unit, run

shutdown -h now
When cut-off is enabled the unit is back to same state as it was when you plugged it in and will start again when any of the start signals goes high.

Read start signal⚓︎

To read this signal you must first unbind it from gpio-keys or read it from /dev/input/event1.

Example read with unbind gpio-key Note: This will disable wake-up possibility on digital and start signals.

echo gpio-keys > /sys/bus/platform/drivers/gpio-keys/unbind
gpioget $(gpiofind IN_START)
echo gpio-keys > /sys/bus/platform/drivers/gpio-keys/bind