VGA/视频适配器解决方案(含源程序代码)

Simple VGA/Video adapter
(This project is about creating VGA/Video signals using the 8-bit AVR MCU)
Background of the project.
Several months ago I tried to connect a microcontroller system to a VGA monitor to output data in the
form of text. I was surprised to find little on this subject on the internet, to assist me in achieving this
goal. Certainly nothing simple a beginner could find useful.
There are examples out there that utilise standards such as PC-104 or complex FGPA implementations
found at www.opencores.org. Other solutions include graphic controllers from Fujitsu or even one local
Russian person who was offering for sale a project for $5000 on ACEX. These are fine but are little help
to most hobbyists etc out there who wish to display text on a VGA or similar screen.
What I desired was a “quick and dirty” solution that did not cost too much.
Initial calculations showed that the the AVR 8-bit microcontroller from ATMEL, with its 16Mhz clock
speed providing approximately 16 MIPS was a good candidate for further research. Also note that newer
AVRs such as the Mega48, Mega88 and Mega168 will officially support clock rates upto 20 Mhz.
Therefore I concluded that with a clock of 16 Mhz I could achieve something in the order of 8 Mhz
speed of data being transferred out of a port. I also chose the AVR as I had already built up quite a body
of experience with it and so I began work of the project.
After approximately two to three months of research, I present you the fruits of my labour