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Discussion Starter · #1 ·
I am trying to create 960X540p res for HDTV display with a horizontal refresh rate at 33.75 khz . I have read that 540 should have a total of 563 lines I also read this:



quote:

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Originally posted by anevard

[ The formula I have for calculating horizontal sweep is:


Horizontal Scan Rate = Pixel Clock Rate / Total Horizontal Pixels


Andrew [/b]

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If I am right this means,


1376 total horizontal lines divided by a pixel clock of 40.785 = 33.737


This is what I am looking for right? As close to 33.75 as I can get or do I need to change porch and sync settings until I get an exact 33.75?


Thanks for any help
 

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It varies by manufacturer. For example, my Mits syncs perfectly at 33.5KHz. Open Windows Explorer and adjust the scan rate until the edges are converged correctly. Then adjust the porches to fit to width, while maintaining the same scan rate. When you decrease the horizontal porch values, you increase horizontal overscan. The porch settings are really to adjust the blanking area.

I posted my Mits timings in an earlier post this morning, 848x480p using 540p timings for desktop use and 1440x480p for DVD.

Why 480p at 540p timings? If use you 540p at 540p timings you get a lot of vertical overscan. 480p at 540p timings gives you 480 visable lines and the other 60 lines goes to the vertical blanking area.
 

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Discussion Starter · #3 ·
Ahh, smaler porch = bigger image, Thanks! I can find very little information about porch's and sync settings.


I will try 480p vs 540p to see which gives me the better image.
 
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