MiSTer FPGA Forum

I made some modifications to the Vectrex core to get XYZ output from the VGA port for an oscilloscope.

Here is my github fork with some more details and pictures:

https://github.com/Jokippo/Vectrex_MiSTer_XYZ

I included Gerbers and STLs so you can make your own adapter if you have some electronics knowledge.

Videos of it in action:
https://youtu.be/6vOpB0jy7xM
Lightpen:
https://youtube.com/shorts/xjpVvosmDCY

Amazing!

This is great! I was wondering years ago if something like this would be possible. I guess with the new analog IO boards, with 24-bit VGA output, this could work even better?

Some games I remember using variable brightness (Z output) are: Mine Storm, Web Warp and Dark Tower.

I have a Vectrex, but also a CRT scope, it would be fun to try this.

LamerDeluxe wrote: ↑Tue Apr 02, 2024 3:58 pm

This is great! I was wondering years ago if something like this would be possible. I guess with the new analog IO boards, with 24-bit VGA output, this could work even better?

Some games I remember using variable brightness (Z output) are: Mine Storm, Web Warp and Dark Tower.

I have a Vectrex, but also a CRT scope, it would be fun to try this.

The signal is already good enough on 18-bit I think, PWM would still be needed on the 24-bit boards. But it might look a little better yeah, especially if the 24-bit boards have better linearity.

Wow, that is awesome. With lightpen input from the oscilloscope? How is that even possible?

That is wild! One day would love to see it possible to use the mister cores to play on vector monitors (ie. asteroids, battlezone, etc).

syn wrote: ↑Tue Apr 02, 2024 5:58 pm

Wow, that is awesome. With lightpen input from the oscilloscope? How is that even possible?

The light sensor is just directly attached to an interrupt pin on the cpu through the user port, just like the real Vectrex. If the sensor is triggered while the program is drawing the lines of the little cursor, the vectrex software will know the position of where the pen is held. There is no additional latency from the XYZ output so it will just work as expected.

Just found this too: https://youtu.be/-o5zJ1T778g It would be very cool to make a Vector monitor and MiSTer cores for it.

This is better
https://www.youtube.com/watch?v=LNXurZhrZ_Y

And you get colour vectors using this method. Just wish I had the knowledge, and the balls to do myself, but even though I have many CRTs, they still scare the crap out of me.

Man I so want that. I actually made my own arcade cabinet in the theme of the Star Wars vector arcade cabinet with a rotatable CRT in it. I wonder if I could hodgepodge a vector / raster mode switch into it. That would be totally amazing if I could get Star Wars working in vector mode and still be able to play Donkey Kong, etc. in raster mode. Of course, we need a Star Wars core first.

I don't think you could switch between vector and raster because you have to rewind/rewire the yoke. Also, I think he's using a custom controller board that only excepts X, Y, Z axis inputs, so no RGB for raster.
I would pay a good amount of cash for someone, or some company, to mass-manufacture vector monitors, but sadly I think those days are long gone. And, I don't think anyone wants to rework raster CRTs to Vector, to sell to the public.

If I have to rewind the yoke, then definitely it wouldn't be possible. I was thinking of having separate electronics boards both wired up and just power one on at a time or something like that.

Ruleset wrote: ↑Tue Apr 02, 2024 4:19 pm

The signal is already good enough on 18-bit I think, PWM would still be needed on the 24-bit boards. But it might look a little better yeah, especially if the 24-bit boards have better linearity.

Sorry for the bump on this old thread, but I just ran across this, and I am impressed at how elegant your method is. Are there enough outputs on the VGA port to drive a color vector screen? I've always understood the Vectrex was the slowest vector. Things like the Star Wars Death Star explosion on Atari, and some of the effects that Sega did with their vectors require faster speeds. Do you know if they require higher bitrates too? Does the bitrate dictate the points on the screen or the amount of redraw required? Have you looked at any of the arcade vectors on MiSTer with your adaptation?

What a bloody good idea!!! Good luck with it.

pashdown wrote: ↑Fri Aug 30, 2024 4:52 am

Sorry for the bump on this old thread,

No problem, I am just happy someone else is interested in this tbh.

pashdown wrote: ↑Fri Aug 30, 2024 4:52 am

but I just ran across this, and I am impressed at how elegant your method is. Are there enough outputs on the VGA port to drive a color vector screen? I've always understood the Vectrex was the slowest vector. Things like the Star Wars Death Star explosion on Atari, and some of the effects that Sega did with their vectors require faster speeds. Do you know if they require higher bitrates too? Does the bitrate dictate the points on the screen or the amount of redraw required? Have you looked at any of the arcade vectors on MiSTer with your adaptation?

This circuit is made to be used with oscilloscopes. Pure vector CRT's would probably need additional circuitry. I do think the VGA port has enough output pins to do color but only at binary intensity. I don't know how much faster the current circuit can draw lines, the max drawing speed is a balance between higher capacitance to smooth out the PWM and lower to make the beam more responsive. This bit depth is probably sufficient for the arcade games but the beam speed may not be, I can try to port it over to the other vector cores at some point.