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Connect to USB Camera(FA-CAM202)

The FA-CAM202 is a 200M USB camera. You can refer to <Connect DVP Camera (CAM500B) to Board> on how to connect a USB camera to a board.
You need to change the start.sh script and make sure it uses a correct /dev/videoX node. You can check your FA-CAM202's node by running the following commands:

$ apt-get install v4l-utils
$ v4l2-ctl -d /dev/video1 -D
Driver Info (not using libv4l2):
        Driver name   : uvcvideo
        Card type     : HC 3358+2100: HC 3358+2100
        Bus info      : usb-1c1b000.usb-1

Information above indicates that /dev/video1 is the device node of the FA-CAM 202.

Check CPU's Working Temperature with Commandline Utility

You can get CPU's working temperature by running the following command in a commandline utility:

$ cpu_freq
CPU0 online=1 temp=26581 governor=ondemand cur_freq=480000
CPU1 online=1 temp=26581 governor=ondemand cur_freq=480000
CPU2 online=1 temp=26581 governor=ondemand cur_freq=480000
CPU3 online=1 temp=26581 governor=ondemand cur_freq=480000

This message means there are currently four CPUs working. All of their working temperature is 26.5 degree in Celsius and each one's clock is 480MHz.

Check System Information with Rpi-Monitor

Our OS contains the Rpi-Monitor utility with which users can check system information and status.
In our case our board's IP was and we typed the following IP in a browser:

We were directed to the following page:
Users can easily check these system information and status.

Test Watchdog

You can test watchdog by running the following commands:

$ cd /root/demo/watchdog/
$ gcc watchdog_demo.c -o watchdog_demo
$ ./watchdog_demo /dev/watchdog0 10
Set timeout: 10 seconds
Get timeout: 10 seconds
System will reboot in 10 second

System will reboot in 10 seconds.

Test Infrared Receiver

Note: this only applies to boards(such as NanoPi M1, NanoPi M1 Plus and etc) that have an infrared receiver. If you want to test boards(such as NanoPi NEO, NanoPi NEO Air and etc) that don't have an infrared receiver but have infrared pins you need to connect an infrared module to pin GPIOL11.
By default the infrared function is disabled you can enable it by using the npi-config utility:

$ npi-config
    6 Advanced Options     Configure advanced settings
        A8 IR              Enable/Disable IR
            ir Enable/Disable ir[enabled]

Reboot your system and test its infrared function by running the following commands:

$ apt-get install ir-keytable
$ echo "+rc-5 +nec +rc-6 +jvc +sony +rc-5-sz +sanyo +sharp +mce_kbd +xmp" > /sys/class/rc/rc0/protocols   # Enable infrared
$ ir-keytable -t
Testing events. Please, press CTRL-C to abort.

"ir-keytable -t" is used to check whether the receiver receives infrared signals. You can use a remote control to send infrared signals to the receiver. If it works you will see similar messages as follows:

1522404275.767215: event type EV_MSC(0x04): scancode = 0xe0e43
1522404275.767215: event type EV_SYN(0x00).
1522404278.911267: event type EV_MSC(0x04): scancode = 0xe0e42
1522404278.911267: event type EV_SYN(0x00).

Access GPIO Pins/Wirings with WiringNP

The wiringPi library was initially developed by Gordon Henderson in C. It contains libraries to access GPIO, I2C, SPI, UART, PWM and etc. The wiringPi library contains various libraries, header files and a commandline utility:gpio. The gpio utility can be used to read and write GPIO pins.
FriendlyElec integrated this utility in FriendlyCore system allowing users to easily access GPIO pins. For more details refer to WiringNP WiringNP

Run Qt Demo

Run the following command

$ sudo /opt/QtE-Demo/run.sh

Here is what you expect to observe. This is an open source Qt Demo: