VIA Technologies VAB-820 - Real-Time Clock (RTC) Management

VAB-820 Linux BSP v3.2.0 Quick Start Guide
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$ echo "in" > /sys/class/gpio/gpio7/directio n
To read the GPI input value, use the following command:
$ cat /sys/class/gpio/gpio203/value
5.10.3. Setting Up GPO Mode
To set a pin to “output” mode (GPO), use the following command (here is the example
for GPIO pin 1):
$ echo "out" > /sys/class/gpio/gpio7/direction
To output a “Low” value on the GPO pin, use the following command:
$ echo 0 > /sys/class/gpio/gpio7/value
To output a “High” value on the GPO pin, use the following command:
$ echo 1 > /sys/class/gpio/gpio7/value
5.11. Configuring RTC
As the first step, set the system time with the Linux date command, for example as:
$ date mmddHHMMYYYY
Time Value
mm 2-digit month
dd 2-digit day
HH 2-digit hours in 24h system
MM 2-digit minutes
YYYY 4-digit year
Time value table
For example, the value 061110072013 means June 11 2013 10:07. The date command
also accepts other time formats. For more information, use the following command:
$ date --help
To write the system time to the RTC, use the following command:
$ hwclock -w -f /dev/rtc0
To read the RTC time, use the following command:
$ hwclock -r