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Dvk521 User Manual

Document formatting convention

  • Commands on PC ubuntu terminal: preceding with '#'
  • Commands on SD card linaro terminal: preceding with '$'

Burning the Testing Image

A pre-configured image is provided for testing, follow the steps below to burn it into the SD card:

1. format the SD card by using HPUSBDisk

2. Select the target image cb1-dvk-sdcard-lubuntu-lcd v1.0.img,click 'Write' to burn it into the SD card by Launch Win32DiskImager

3. Default user: linaro,Default password: linaro,The root permission password: 123456

API and Drivers Source code

  • The API and Drivers source code of DVK521 can be found on
  • Also are accessible in the SD card image:
    • /home/linaro/waveshare_demo/

Since driver compiling relies on the kernel, if you need to compile our source code, you should modify the related Makefile according to your own kernel path, then execute:

# make

For more info, please refer to the document Driver Porting and Configuration.

Serial Port Monitor

Install serial port monitor on ubuntu

Note: here we are talking about how to use serial port on ubuntu installed via wubi. As for using serial port on ubuntu on virtual machine, some wired problems may occur.

Connect the DVK521 to PC through a USB cable. Connect the →RX, ←TX on DVK521 respectively to TX, RX on Cubieboard via jumper wires.

Use the following command to check if USB0 or USB1 exists:

# ls /dev/ttyUSB*


Use the screen command to establish connection:

#screen /dev/ttyUSB0 115200

You may want to install the screen command first in case it doesn't exist:

#apt-get install screen

If the Cubieboard has started up, press Enter key to enter command terminal, the default user should be root. In case nothing happens when pressing Enter, try to disconnect and reconnect the USB port on Cubieboard, execute the following command again:

#screen /dev/ttyUSB0 115200

Press Enter until any info displayed on the serial port monitor. If you enter the command terminal via VAG or HDMI other than serial port, then the default user should be linaro, the default password should also be linaro.

Install serial port monitor on Window

The serial port driver is required for Window. DVK521 integrates the PL2303 USB-to-UART convertor. To install the serial port driver, double click the install package which can be found on PL2303_Prolific_DriverInstaller_v1.8.0. When completed, connect the PL2303 to PC through a USB cable, the PC will try to detect device. To ensure the detection succeeds, please close the anti-virus software or other computer protection software. When the device is detected successfully, install the serial port monitor ultra-serial-port-monitor.


Burn the provided image into your SD card, when the system startups, connect the board to PC through a USB-to-serial-port cable, then launch the console terminal. The root permission should be gained by default. In fact, all of the following demos are running under root permission. In case any command can't be executed or any error occurs, it might be that you are not proceeding under root permission, try to switch user using the following command:

$ su  root  

Then enter the password:

$ 123456  

It is recommended that disconnect every module after testing to avoid port conflicting.

HDMI, LCD, VGA Display Mode

At any time, only one of the three display mode is available. The default option is LCD mode, use related command to select other display mode. For VGA mode, use:

$ test_vga  

For LCD mode , use:

$ test_lcd  

For HDMI mode, use:

$ test_hdmi  

After executing the above commands, the board will reboot automatically to apply the new display mode.

About the LCD Touch Screen

  • When the system startups and the operation interface is displayed, wait for seconds before touching the capacitive screen.
  • When touching the folder icon, the mouse will move to the target position after seconds.
  • When touching the blank section, the mouse will not move, instead, a small cursor will show up on the touched position. Keep pressing the screen on any blank section and slide to perform box section.
  • After entering the folder on the screen, the mouse will keep following the touch action.

OV7670 Demo

Connect the OV7670 module into the OV7670 interface, connect the 7inch capacitive touch LCD. Enter the following command on the console terminal:

$ test_camera  

The video stream is supposed to be seen on the LCD, and the focal length is also adjustable (in case the screen becomes messing up, reboot the system). Press Ctrl+C to stop.


  • 1. If the OV7670 demo is tested after other demo, the screen will be messing up. Therefore, it is recommended to test the OV7670 demo first when the system startups.
  • 2. After the OV7670 demo, the half of the screen will become white, which might be caused by insufficient memory. Press the white screen section to recover, or reboot the system.
  • 3. The OV7670 module and the push button module share certain same pins, disconnect the OV7670 module while testing the push button.
  • 4. Video stream from the OV7670 module supports LCD display mode only, doesn't support VGA display mode.

LED Demo

Short the onboard LED jumpers. Enter the following command:

$ test_led   

You will see the 8 LEDs light up one by one every second. Press Ctrl+C to stop.

8 Push Buttons Demo

Connect the 8 Push Buttons accessory board to the onboard 8I/O s interface (The OV7670 module and the push button module share certain same pins, disconnect the OV7670 module while testing the push button). Enter the following command:

$ test_key   

Press any of the 8 push buttons, related value will be displayed on the console terminal. Press Ctrl+C to stop.

Buzzer Demo

Short the onboard buzzer jumper. Enter the following command:

$ test_buzzer  

The buzzer will start to make sound and stop later.

Note: if the buzzer keeps making sound, disconnect it from the board.

DS18B20 Demo

Insert the DS18B20 into the 1-WIRE socket, short the onboard 1-WIRE jumper (ensure that the AT45DBXX DataFlash Board has been disconnected). Enter the following command:

$ cd /sys/bus/w1/devices/   
$ ls  

There's a folder with the name looks like "28-0000054a5bec " (the last 7 characters is a unique device ID of every different DS18B20, in this case, the device ID is 54a5bec). Enter the following command:

$ test_ds18b20  54a5bec  

The current environment temperature will be displayed on the console terminal.

AT45DB Read/Write Demo

Connect the AT45DBXX DataFlash Board to the onboard SPI interface Enter the following command:

$ test_at45db  

Data will be read and displayed on the console terminal.

AT24C04 Read/Write Demo

Connect the AT24/FM24 module to the onboard I2C interface. Enter the following command:

$ test_at24c04  –w  

Data will be written into the device and displayed on the console terminal.

$ test_at24c04  –r  

Data will be read from the device and displayed on the console terminal.

tutorials/expansion_boards_dvk/dvk521/documentations/a10/dvk521_user_manual.txt · Last modified: 2014/07/23 10:11 by waveshare