Monthly Archives: February 2021

VoCore Screen: Test on Windows

VoCore Screen is mainly designed for embed Linux, so it is easy to work on Linux or Unix(MacOS), but for windows, it is not that smooth. Windows do not have libusb support directly, so we have to use third party driver to achieve that, like libusbK.

Recently pretty much people use this screen for car race simulator on Windows, so I think it is necessary for me to write a tutorial to show how to fast test if the screen work normal under Windows OS.

First, we need install libusbK for Windows

We already have it in our windows SDK, you can download it at, or use this directly link here:, uncompress it and install the libusbK driver, you can find the device “USB 2.0 Screen” at your “Device Manager”.

Second, try our new test app in SDK.

In, there is one folder named example, used to test the screen.

And we have a test data, frame.dat. So we can directly run send_frame in the example folder in windows command line.

send_frame frame.dat

Then your screen will display the test picture. Test picture should be 480×800 size and 16bit RGB format BMP, remove 139 byte BITMAP header, raw data.

Other Commands Usage


  • usage: send_frame [frame data file]
  • used to send one frame(bmp 16bit format data without bitmap header) to screen.
  • example: send_frame frame.dat


  • usage: read_touch
  • used to read touch screen position and press status, no parameter.


  • usage: send_cmd [cmd] [param]
  • used to send command to screen, control screen rotated or backlight.
  • example: mirror by axis x,y [0,1,2,3] to mode1 send_cmd m 1
  • example: set backlight [0~255] to 120 send_cmd b 120

VoCore Screen: Upgrade

From last year Sep.1, we meet global chip shortage. Recently some chips price increase to incredible level. My chip provider told me, currently STM32F103 price is around 72CNY/pcs(11USD/pcs) compare to early of last year only 3~5CNY. Another network chip IP101G, from 0.8~1CNY to 10CNY. 🙁 This is really crazy.

PS: Lucky, I use Gigadevice MCU, pin to pin STM32 but need to recompile firmware. Its price increased 10%~15%, compare to STM32 chip, looks like it is reasonable and acceptable.

For our production VoCore2 and camera, we have enough stock, but screen driver chip now have problem. The chip factory give me 25~30 weeks lead time, that is over half year. We have to change current screen plan.

New screen is from Toshiba, better color than our old one. In order to compatible with old design, we add a FPC to convert its connector. For order later than Feb.9, we will all ship this screen. In software level they are compatible.

One slight difference, old screen once power on will show a white screen, this new one show black screen as default.

Screen size is almost same as old version(around 0.5mm smaller for both sides) also FPC is bendable, so this design should be compatible to most old screen enclosure.

Finally, here is its photo: