Eurotech BoltGATE 20-25, Руководство пользователя

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10 How to Access the Interfaces Under Linux BoltGATE 20-25 User Manual Rev. 1-1
10.11 The Ignition Key
The Ignition Key is a digital input that enables the system to be turned ON / OFF.
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If Ignition Key = 1 the system turns ON
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If Ignition Key = 0 the system turns OFF automatically after 120 seconds
(by default the shutdown time (timeout) is 120 seconds, but you can modify it)
For more information see "The Ignition Key (Key Signal)" on page 95 .
To read the Ignition Key status, enter the following command:
cat /dev/ignition_key/value
The reply to the command is the following:
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If the Ignition Key is connected to VIN+, you will obtain value = "1"
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If the Ignition Key is connected to GND, you will obtain value = "0".
To read the Ignition Key timeout, enter the following command:
cat /sys/bus/usb/devices/1-5.3:1,.0/ignition_key_timeout
To set the Ignition Key timeout, enter the following command:
echo xx > /sys/bus/usb/devices/1-5.3:1,.0/ignition_key_timeout
10.11.1 Note About CPU Sleep States
By default the CPU cannot enter in the sleep states (S3 or S5) while the Ignition Key is ON.
If the CPU tries to enter in S3 or S5 while the Ignition Key is ON, the cortex will reset the system.
To allow the CPU to enter in S3 or S5 while the Ignition Key is ON, you have to prior notify this action to
the cortex.
To notify the CPU sleep action to the cortex, enter the following command:
echo 0 >/sys/bus/usb/devices/1-5.3:1,.0/cpu_sleep_action
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