How do you transition from one line to the next? Also, you have a certain time to traverse the 640 pixels. If it's required to use 2560 clock cycles, how do you know when you should change the colour of each pixel? Should it be done every 4 clock cycles or every 1 cycle? What I am basically asking is how the VGA knows what pixel to paint within that time it should paint pixels. In the VGA documentation for FPGA, there is no output that is required to show the position of the pixel in either horizontal or vertical plane.
It's an analog protocol, it has no notion of actual pixels. What happens is that during the visible portion the beam just changes intensity for each color according to the R,G,B inputs as it moves to the right end of the screen. The visible portion is normally considered to be 640 pixels but this is just a convention when the signal generator comes from digital circuitry. Since the signal is analog in nature it could be anything, but if the (digital) clock on the VGA signal generator represent one pixel per cycle, as described in the video, then you should set the appropriate R,G,B signals every 1 clock cycle.
I am studying VGA and ISP . so Your video is helpful for me . Thank your for your channel
How do you transition from one line to the next? Also, you have a certain time to traverse the 640 pixels. If it's required to use 2560 clock cycles, how do you know when you should change the colour of each pixel? Should it be done every 4 clock cycles or every 1 cycle? What I am basically asking is how the VGA knows what pixel to paint within that time it should paint pixels. In the VGA documentation for FPGA, there is no output that is required to show the position of the pixel in either horizontal or vertical plane.
It's an analog protocol, it has no notion of actual pixels. What happens is that during the visible portion the beam just changes intensity for each color according to the R,G,B inputs as it moves to the right end of the screen. The visible portion is normally considered to be 640 pixels but this is just a convention when the signal generator comes from digital circuitry. Since the signal is analog in nature it could be anything, but if the (digital) clock on the VGA signal generator represent one pixel per cycle, as described in the video, then you should set the appropriate R,G,B signals every 1 clock cycle.