Yeah, the Video Challenger uses VHS tapes. I have a bunch of tapes for that and similar systems. I had started looking at how to get high quality VHS captures before I got distracted by work and stuff. Maybe I can get back into that soon.
Most systems just play a video and you basically shoot a flashing target to score--not much interactivity. The Interactive Vision is the most complicated one. It can switch between audio tracks based on your decisions, and has places where it uses a visual pattern (almost like a bar code) to load data for simple mini games.
not much to emulate without VHS tapes I'm guessing?
Yeah, I sent 2 COP420's in to dump, both are the same, one from a spare unit, the 3 leds flash when you hit something or it hits you, this reflects off a mirror into the eyepiece of the gun and a 7-seg output on the back of the gun for score. I have still have some tapes, I've ripped them all, some are on YT in parts, the turtles one had an issue with lionsgate holdings so its on archive.org, I can re-rip these any time however, they are terrible. Also have an Action Max PAL version which was never meant to be.
And Bandai Video Challenger: www.seanriddle.com/cop420tdx.bin - a lot of ASCII for a small file: VGUN22 BY STEVE BECK COPYRIGHT 1987 SELECT MERCHANDISE INC. ALL RIGHTS RESERVED CODE MADE IN CALIFORNIA USA!
Here's what I got: G0-G2: all of them? to speaker G3: N/C D0-D2: to a demux chip(which?), to digit select D3: N/C L0-L7: digit segments SK: target hit led IN0: trigger IN3: light sensor IN1,2: N/C
But as Haze said, there's not much to do without the tapes. And even if we have good rips of the tapes, MAME would need a VHS player device first(or a video player device? akin to current device/sound/samples.*). I was able to cheat by adding a strobe timer to the light sensor input, so at least it looks like that part is working.
If the loopy can be powered up and you have at least one game etc. then I might be able to convince Peter to look at it with me, as we should be able to use the same technique to get the internal SH rom as we've used for PGM2 etc.
to which Peter has said, yeah, he'll look at it with me, but it might be next year before it gets done, because we already have a backlog of about 4 projects :-)
that said, I think it's the most effective way of dealing with it because it means we don't have to decap, don't have to try and scribble down random symbols from the screen based on hacked code and little understanding of the video hardware, and we get 100% correct data because we read it electronically by modifying the code execution.
