Altera DE2 Board, Руководство по началу работы

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Lab 3: USB Paint Brush
54
Chapter
7
Chapter 7
Lab 3: USB Paint Brush
USB becomes the most popular communication method in many multimedia
products. DE2 provides users a complete USB solution on both host and device
applications. In this lab, we are implementing a Paint Brush Application with USB
mouse as input device.
7-1
Design Descriptions
In this lab demo, we use the device port of the Philips ISP1362 and NIOSII CPU
to implement a USB mouse movement detector. We also implemented a video
frame buffer with VGA controller IP to perform the real-time image storage and
display. Figure 7.1 illustrates the block diagram of the design, where users can
draw lines on the screen using a USB mouse. The VGA Controller IP block is
integrated into the Altera Avalon bus so that we can use NIOSII CPU to control
the VGA Controller block.
Once the program running on NIOS II CPU is started, the DE2 board will detect
the existence of the USB mouse connected to DE2 board. Once the mouse is
moved, NIOSII CPU is able to keep track the movement and record the
movement in a frame buffer memory. The VGA Controller IP will overlap the data
stored in the frame buffer with a default image pattern and display the overlapped
image on the VGA.