That’s where the blue breakout board comes into play. First off, the sync signal for SCART tends to be rather awful. Technically that’s all you really need to make this happen, but the results will not be good. Now comes the wiring and you may have already noticed that there’s a lot more going on here than the color channels, sync signal, and ground. He grabbed a coupler off of eBay and cracked it open, yielding two connectors. The first step is to source a female SCART connector. But what if you have a SCART connector as an output? That’s the situation in which found himself so he hacked in SCART support. If you’re working with a CGA, EGA, or RGB gaming system this inexpensive board does a great job of converting the signal to VGA so that you can play using a modern display. Posted in Retrocomputing, Video Hacks Tagged lm1881, ntsc, oscilloscope, retrocomputer, texas instruments, TMS9918, TMS9918AA Adding A SCART Input To A Console VGA Converter Or if you want to know more about the mystical properties of analog NTSC video, we’ve covered that, too. Having the right tool can make all the difference, like this homebrew logic meter for hobby electronics troubleshooting. Maybe it will help you in your next vintage computing caper. If this has piqued your interest, also has a great write-up over on GitHub with all the gory details. A tiny OLED display makes configuration easy. Along with a smattering of discrete components, the ATmega aids the user in selecting which line to frame a trigger on, and the slope of the horizontal sync signal to align to. The Video Trigger project uses a LM1881 sync separator to tease out the horizontal and vertical sync signals from the vintage video chip, with the output piped into an ATmega 328P. Maybe a different scope would have solved the problem, but had a feeling that the ‘scope needed an external trigger signal. And without a better understanding of the video signal, it was difficult to use the chip with newer TFT displays, being designed for CRT televisions with more forgiving NTSC tolerances. Substantial retro computing heritage notwithstanding, the video output from this chip was (for reasons unknown) not quite compatible with the Hantek DSO1502P oscilloscope. The Texas Instruments TMS9918 video display controller was used across a range of 1980s game consoles and home computers, from the well-known ColecoVision to Texas Instruments’ own TI-99/4. Their oscilloscope was having trouble triggering on the video signal produced by older video circuitry, so they created the Video Trigger for Retrocomputers. Working on retro computers is rarely straightforward, as recently found out while designing a new display interface.
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