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Altera_Forum
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14 years ago

VGA problem

Hi, Anyone here can help me with VGA problem, the program code just simply output one colour to monitor. However, my monitor display nothing. I have no idea what happen. :( The attachment is my...
Altera_Forum's avatar
Altera_Forum
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14 years ago

I agree with Reuven. Also if you are driving and LCD panel, the timing may be more critical in the system than if you were driving a CRT.

http://www.xfree86.org/3.3.6/config7.html has some video timing standards to look at. Old CRT's were pretty forgiving on this, but LCD's can be pretty tight on the requirement. You usually can get away with a different pixel clock (IE 25 MHz instead of 25.175) but the sync timings have to be pretty close, so you end up eating the front porch/back porch time to make it work.

Pete