The guys at the resistor network has developed an AVR based VGA generator, and the good thing about it is that its open source. The entire source code is available to download. VGA stands for Video Graphics Array and was first developed by IBM around 1987. The generator uses an ATMEGA1284p which has 16KB of ram and 128Kb of program memory. The hardware will be running at overclocked frequency of 25MHz to get 640 clock cycles per line. This allowed a higher resolution time buffer.
The entire VGA generation and buffer is implemented in assembly under the GNU tool chain. The only problem with this version of VGA generator it has no scope for dynamic graphics and that is what has to be developed in the upcoming version. For generating dynamic graphics, there will be a need of another microcontroller that will send commands to the VGA controller. The project has a RGB222 colour gamut which has a space for 64 colour each of the colour occupying two bits with 6 and 7 bit as unused. One could even use all the bits but it might make generation of grey colours a lot difficult.
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