Tempest help

Hi Nethawk86, I'm wondering if you can comment some more on how your Tempest image became mirrored, and exactly how you fixed it.

I'm looking into reversing mine on purpose for use in a mirrored cabinet. Thanks!

If you want to force your board to mirror the image, there are two pins on the edge connector that do this. See the pic from the schematic below. The board outputs two signals (OUT3 and OUT4), which are looped back into the board, and control the X INV and Y INV signals, which flip the X and Y axes of the image (via other circuitry in the video section).

If you want to control these manually, you just need to cut those two wires (or pull the pins from OUT 3 and OUT 4, so you don't have to cut the wires), and rig up two switches that let you either ground X INV and Y INV, or let them float. (in which case they'll be pulled high by the board). Then you can use the switches to manually flip either axis.

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You could also flip either axis at the yoke (not using the RGB signals, but rather the wires on the deflection board that actually drive the yoke, on the 4-pin connector that goes to the yoke. They're actually red, blue, yellow, and black.) Red and blue control one axis, and yellow and black control the other. So swapping red with blue will flip one axis, and flipping yellow with black will flip the other.
 
Cool project, BTW. I've always thought Tempest would be a good candidate for a mirrored setup with a deep-space background.

I remember your comment about this from a while back, on a previous thread. :)
 
Still waiting for Nethawk86 to chime in on how he resolved it. He said "it was the J connector on the harness." To me that sounds like the J pin on the game pcb harness. Does that mean that his image flipped when the J pin (OUT 3) on the harness didn't make contact with the board? Wondering if that sounds right, based on what he described.
 
Still waiting for Nethawk86 to chime in on how he resolved it. He said "it was the J connector on the harness." To me that sounds like the J pin on the game pcb harness. Does that mean that his image flipped when the J pin (OUT 3) on the harness didn't make contact with the board? Wondering if that sounds right, based on what he described.

Pins K and S (Y INV) are normally set high by the board/CPU, for an upright cab. Pins J and 15 (X INV) are normally set low. (I just checked these in my upright.) So removing the pins for either J or 15 at the edge connector (or cutting the wire that ties them together) will flip the image horizontally, as the X INV signal will be pulled high by the pullup resistor on the board. (And that's what happened in Nethawk's case, as his wire was broken or not making contact, so X INV was going high and flipping the X axis.)

Pin K/S (Y INV) is normally high in an upright. You can pull that one low by tieing it to ground with a jumper (which can be done by grounding pin 9 of the LS04 at J11), which will override whatever the board wants to do. You can't use the same trick for X INV however, as it's already driven low by the CPU. So you need to disconnect that one from the board controlling it (which will let it go high from the pullup resistor that already exists on the board, which ties the signal to +5V, so it will go high if nothing is actively driving it low.)

So depending on what you are trying to do, you can just add switches to flip either axis however you want. Or you can move the wires in whichever axis of the yoke you want to flip, which is arguably less work, but doesn't let you control them with a switch. It also hardwires them however you have them (in which case you should label the yoke connector to indicate that you modified the pinout, so you don't confuse someone down the road).
 
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Cool project, BTW. I've always thought Tempest would be a good candidate for a mirrored setup with a deep-space background.

I remember your comment about this from a while back, on a previous thread. :)

This is one I've also wanted to see done for some time.

Is that what you're doing? If it comes out as nice as I imagine it potentially could, it's something Atari arguably should have done originally. The premise of the game is that the tubes are floating in space, so it makes perfect sense. I just don't know how the colored vectors will look through the mirror.

I'm also curious what you'd do for any cardboard background/artwork, like the AD cab has. (Though you could maybe just leave it black, too.) But there are all sorts of ways you could go with that. You could make stars or some kind of space theme. Or have cutouts of the various enemies, blown up a bit. The choice of blacklight color and brightness will also play a role. Though I almost think no cardboard background or blacklight would look cool too. (Just make the playfield float in space, with no other effects.)

I'm jealous if you're actually going to do it. We definitely need a project thread to follow along!
 
This is one I've also wanted to see done for some time.

Is that what you're doing?

Shh...not so loud! :) But I've already spilled the beans, so...

Yes, I'm working on what you might call Tempest Deluxe...rearranging the inside of a newly-built Tempest cabinet so it'll accept the mirror + backdrop setup (using AD as the template). Then swap in the "innards" from my existing Tempest and test it out. Nothing built yet, but I'm shooting for CNC work to be done in June.

I just don't know how the colored vectors will look through the mirror.

I think they'll look spectacular! If the side grooves are done right, the bezel and tinted glass could still go over the picture tube. Or perhaps keep the tinted glass as the "viewscreen," depending on visibility into the cabinet. If it's too opaque, then use a clear plexi or clear glass piece.

I'm also curious what you'd do for any cardboard background/artwork, like the AD cab has. (Though you could maybe just leave it black, too.) But there are all sorts of ways you could go with that. You could make stars or some kind of space theme. Or have cutouts of the various enemies, blown up a bit. The choice of blacklight color and brightness will also play a role. Though I almost think no cardboard background or blacklight would look cool too. (Just make the playfield float in space, with no other effects.)

This has to be very carefully done—there's so much visual information in the center of the screen in Tempest that a "busy" backdrop design could ruin the gameplay. Anything behind the vectors has to be very subtle. So I'm thinking that around the edges of the screen would be the way to go with more elaborate artwork and blacklight effects.

Also, the back of the Tempest cabinet may be too shallow for the mirror/backdrop, so it's all somewhat tentative at this point.

Still, it's a very exciting experiment, and I look forward to reporting back on it!

I'm jealous if you're actually going to do it. We definitely need a project thread to follow along!

:) I'll make a new thread when things develop a little further.
 
Shh...not so loud! :) But I've already spilled the beans, so...

Yes, I'm working on what you might call Tempest Deluxe...rearranging the inside of a newly-built Tempest cabinet so it'll accept the mirror + backdrop setup (using AD as the template). Then swap in the "innards" from my existing Tempest and test it out. Nothing built yet, but I'm shooting for CNC work to be done in June.

So wait, you're trying to put a mirror in a Tempest cab? Interesting.

Is it deep enough? Or are you redesigning the cab to make it deeper? You're going to mount the monitor facing upwards and get a mirror in there? I'm curious how that fits. It seems like you'd need to redesign the entire interior of the cab. But I'm also not sure how you'll get a mirror in such a shallow cab.

I've always imagined doing Tempest in an AD cab, as you have the depth, and the dimensions are mostly there (though you'd be mounting the monitor the other way, 'vertically', which might change the layout of the innards.)

Lots of variables to play with, to get everything just right. I'll be interested to see how this goes, for sure. But the end result should be worth it, if done right. Just seeing the tubes float in space will be awesome. (And the zooming effect between screens should look really cool.)
 
I think it's possible in a Tempest cab, but if not then we'll try it in an AD. Either way it'll look amazing!

Yes, the interior of the Tempest would have to be completely redesigned to make it work. And it may not be deep enough as designed, certainly not as deep as AD. So yeah, adding a few inches to the back of the cabinet may be necessary.

If it did work out, then Tempest owners could swap into the newly-built "Tempest Deluxe" cabinet for a while and then back into their original Tempest cabinet.
 
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