Driver for VGA on the DE0
The DE0 has a VGA connector that is connected to a 12bit (4bit per color) resistor ladder DAC. Driver displays at 1280x1024 @ 60Hz.
Pressing no buttons will display a pure white screen.
Pressing BUTTON0 will push the combination of SW0 - SW9 into the display register. Flipping the toggle switches (SW0-SW9) will change the color in the this mode.
Pressing BUTTON1 shows a horizontal color pattern test.
Pressing BUTTON2 shows a vertical color pattern test.
DE0_VGA.v takes care of the driving the signals. The top level looks at the position of X_pix and Y_pix and figures out what to put on the pixel_color bus.
Quartus II V13.0 Project file: DE0_VGA.qpf