NanoPi NEO Core2 添加外部RTC时钟并开机读取

	Mini Shield for NanoPi NEO Core/Core2
SDA	Pin3
SCL	Pin5
5V	Pin4
GND	Pin6

$ apt-get update && apt-get install git

$ git clone https://github.com/friendlyarm/matrix.git

$ cd matrix

$ make -j4

$ sudo make install

$ sudo nano /etc/modprobe.d/matrix-blacklist.conf

删除 blacklist rtc_ds1307

$ sudo nano /etc/rc.local

在exit 0前添加 /sbin/hwclock -s -f /dev/rtc1