RGB Video Cleanup (SNES)
There are many revisions of SNES and many video related issues that need fixing.
Below will be a list of fixes for all console revisions that need it, and how to fix each issue.
This revision can get perfect RGB output with zero faults with the fixes below.
The blur at the edges of pixels from left to right is caused by an inherent low-pass filter inside the PPU2. This can be corrected and sharpened up with the EdgeBuster we sell.
This is caused from what I have gathered so far in relation to the data bus.
If you add back data bus traffic to the output video signal using a 47k resistor to super-impose it you will see the distinctive vertical band and random noise patterns.
Moreover, if you go to 240p test suite homepage and scroll up and down you will see the grey background react to the data bus change.
I have yet to find a solution to remove this noise but will add it here once solved.
This is caused by the chroma clock (3.58MHz) on PPU2 pin 3, and Dot Clock (!5MOUT) on PPU2 pin 27.
NOTE: You will not see this static checkberboard pattern until you fix the vertical center band and moving checkerboard pattern which are much stronger interference.
Underneath PPU2 are the traces in question that add noise to the RGB traces.
Purple is the 5MHz clock, and yellow is the 3.58MHz clock.
You can see they run alongside the R and G traces.
Cut the chroma trace at the start and at the end where it meets R29, and then solder a wire between the two points, bypassing the original trace.
For the 5MHz clock, just turn the resistor, attach a wire, then cut the trace at the end where it meets the R38 empty pad, and then solder a wire between the two points, bypassing the original trace.
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