Nintendo for some reason decided to invert their video signal. What??? It doesn’t make much sense why they did this, they also put the audio amp on the monitor as well. So if you have a bad CRT and try to put a standard monitor in the machine you are stuck with purchasing an adapter to alter the video signal to bring it to a standard. There are adapters made that will adapt both the video signal and have a small audio amp to complete the transition.
But these adapters are not 100% effective. Flat panel monitors are very picky about their sync signals. Left out is punch out and Popeye that we know of. Here at Dayton arcades and more we are researching this issue and working on a solution. We are pretty sure we understand the problem.
(Technical stuff below)
We have analyzed the horizontal sync pulse between a standard arcade game and the one punch-out generates. We found that the sync pulse is only about 30 uS a standard output looks to be about 60 uS. The frequency of the Horizontal and Vertical are right on. We think if we can lengthen the horizontal pulse to 60 uS we can make the unit sync up. But we are afraid that the video signal might not line up with the pulse. Delaying the video signal is a bigger challenge because we must store that information for 30 uS to match up with the sync pulse. Our thought is to use an Arduino and create a program to preform pulse extension and the video delay. Since the Arduino does not have an a/d converter we will have to add 6 of them 2 for each color one in and one out. This project is still a concept. My biggest concern is that there will be too many clock pulses required to read and write the data fast enough to keep up with the video stream. It needs to be precise.