设计了基于LPC1300通用串行总线(USB)及USB设备的发光二极管(LED)显示屏控制卡。通过上位机对将要显示的内容（包括图像和文字）提取位图信息，经过适当的算法对提取到的信息进行变换，从而得到点阵信息。而且，上位机可以设置控制卡的相关参数，例如字体大小、字体类型以及动态效果等。此后，上位机通过USB将相关信息发送给控制卡，控制卡读取缓冲区的内容，进行适当处理后，驱动LED屏显示内容。

The controlling card for light-emitting diode (LED) display screen is designed based on LPC1300 universal serial bus (USB) and USB device. From the content (including image and text) to be displayed, the host computer extracts the bitmap information. Lattice information is obtained by transforming the extracted information with an appropriate algorithm. Moreover, the host computer can set up relevant parameters of the controlling card, such as font size, font type, dynamic effects, and so on. The related information sent to the controlling card through USB. The controlling card reads and deals with the contents in the buffer,and drives the LED screen to display the contents.