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1 Connect to USB Camera(FA-CAM202)

The FA-CAM202 is a 200M USB camera. Connect your board to camera module. Then boot OS, connect your board to a network, log into the board as root and run "mjpg-streamer":

$ cd /root/C/mjpg-streamer
$ make
$ ./start.sh

You need to change the start.sh script and make sure it uses a correct /dev/videoX node. You can check your camera's node by running the following commands:

$ apt-get install v4l-utils
$ v4l2-ctl -d /dev/video0 -D
Driver Info (not using libv4l2):
        Driver name   : uvcvideo
        Card type     : HC 3358+2100: HC 3358+2100  / USB 2.0 Camera: USB 2.0 Camera
        Bus info      : usb-1c1b000.usb-1

The above messages indicate that "/dev/video0" is camera's device node.The mjpg-streamer application is an open source video steam server. After it is successfully started the following messages will be popped up:

$ ./start.sh
 i: Using V4L2 device.: /dev/video0
 i: Desired Resolution: 1280 x 720
 i: Frames Per Second.: 30
 i: Format............: YUV
 i: JPEG Quality......: 90
 o: www-folder-path...: ./www/
 o: HTTP TCP port.....: 8080
 o: username:password.: disabled
 o: commands..........: enabled

start.sh runs the following two commands:

export LD_LIBRARY_PATH="$(pwd)"
./mjpg_streamer -i "./input_uvc.so -d /dev/video0 -y 1 -r 1280x720 -f 30 -q 90 -n -fb 0" -o "./output_http.so -w ./www"

Here are some details for mjpg_streamer's major options:
-i: input device. For example "input_uvc.so" means it takes input from a camera;
-o: output device. For example "output_http.so" means the it transmits data via http;
-d: input device's subparameter. It defines a camera's device node;
-y: input device's subparameter. It defines a camera's data format: 1:yuyv, 2:yvyu, 3:uyvy 4:vyuy. If this option isn't defined MJPEG will be set as the data format;
-r: input device's subparameter. It defines a camera's resolution;
-f: input device's subparameter. It defines a camera's fps. But whether this fps is supported depends on its driver;
-q: input device's subparameter. It defines the quality of an image generated by libjpeg soft-encoding;
-n: input device's subparameter. It disables the dynctrls function;
-fb: input device's subparameter. It specifies whether an input image is displayed at "/dev/fbX";
-w: output device's subparameter. It defines a directory to hold web pages;

In our case the board's IP address was We typed in a browser and were able to view the images taken from the camera's. Here is what you would expect to observe:

2 Check CPU's Working Temperature

You can get CPU's working temperature by running the following command:

$ cpu_freq 
Aavailable frequency(KHz):
        480000 624000 816000 1008000
Current frequency(KHz):
        CPU0 online=1 temp=26548C governor=ondemand freq=624000KHz
        CPU1 online=1 temp=26548C governor=ondemand freq=624000KHz
        CPU2 online=1 temp=26548C governor=ondemand freq=624000KHz
        CPU3 online=1 temp=26548C governor=ondemand freq=624000KHz

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 624MHz.
Set CPU frequency:

$ cpu_freq -s 1008000
Aavailable frequency(KHz):
        480000 624000 816000 1008000
Current frequency(KHz):
        CPU0 online=1 temp=36702C governor=userspace freq=1008000KHz
        CPU1 online=1 temp=36702C governor=userspace freq=1008000KHz
        CPU2 online=1 temp=36702C governor=userspace freq=1008000KHz
        CPU3 online=1 temp=36702C governor=userspace freq=1008000KHz

3 Test Infrared Receiver

Note: Please Check your board if IR receiver exist.
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).

4 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: