Conclusion
And this is how everything ended up looking:
As you can see, my woodworking skills aren't as good as my soldering skills... but the
construction at least doesn't fall apart easily and will protect the electronics nicely.
So, does it actually work? Mostly. The joystick I chose isn't ideal (luckily, I can still connect the Playstation controller and use that to play) and the image still has some interference from the CRTs high voltage generator, but all in all I don't think the result is too bad for something I began just to get into VHDL a bit more.
As usual, you can download the VHDL source code of my implementation of the Black Widow hardware. Everything I made is licensed under the GPLv3, the Pokey- and 6502 implementation have their own license clausules. The code is written for the Xilinx Virtex-2 but should compile for other Xilinx FPGAs too. Apart from the PLL and RAM/ROM (which use Xilinx-specific primitives), the code should be easily portable to Altera or other brands of FPGA too. Ofcourse, I can't distribute the ROMs; you should obtain these yourself and then convert them to VHDL using the tools in the source package.
A final word of thanks goes out to Claude Schwarz. If he hadn't helped me with the analog part, I'd probably still wondering why my vectors are all crooked.
« Prev 8
25 commentsHi, Thanks for your great work on this! Would you please release your source code under the same license that MikeJ originally used not GPL. This will allow MikeJ and others to benefit by the inclusion of black widow in the replay fpga project without contaminating the svn source code with GPL. It seems kind of unfair that you would benefit from his extensive work, but he can't benefit from yours because you changed the license...
Reduced windings of Ferrite yoke coil. But are the two halves wired in series, parallel, or anti parallel?
i have been trying to build a similar console. Couldn't get usable deflection. But maybe now Thanks!
Ah, that seems to be a typo. I just opened the thing up again; the opamps are LM675 chips, not LM685. I've changed it in the text.
Where did you find an LM685? I can't seem to find any data on this audio amp.
+++ I like it a lot! +++
No need to worry about producing x-rays with the CRT, it's actually extremely difficult. CRTs are made out of lead glass that absorbs radiation, and the typical anode voltages for small CRTs in the range of 8-12kV is far too low to generate x-rays with enough energy to penetrate even ordinary glass. X-ray tubes typically don't start emitting any useful amount of radiation until beyond about 40kV and even if you greatly overdrive the CRT, you will burn the shadow mask and crack the glass before it puts out much. On another topic, indeed Gravitar is a simple ROM swap to Black Widow hardware. Black Widow exists because Gravitar was widely hated so Atari released a field conversion kit. BW is a much better game BTW.
Very cool. I'm building a small B&W vectrex like console using a crt and an arduino. I'm going to use your amplifier design.
Upon reflection I suppose that\'s kind of a dumb question as you\'ve done most of that out side of the FPGA
How practical would it be to construct a device that took the digital output from a real cinematronics or sega vector game PCB and converted it to an analogue signal a g05 or similar analogue vector monitor could handle?
I\'ve actually been wanting to take a shot at the Cinematronics machines. They all use a variation of the same hardware (the CCPU) so by building that I should be able to run a whole bunch of games with relative ease. It\'s quite a lot of work, though: in contrast to the 6502, I don\'t know of a VHDL implmenentation of the CCPU I could start with so I\'d have to start from scratch.
Very impressive. Have you considered taking a look at the sega and cinematronics vector games? There are a few people (me for example) who\'d love to play these in their Atari game cabs with analogue vector monitors but the original boards had the digital to analogue conversion circuitry built into the monitor making it impossible to swap and rewire the boards. But one of these boards with the DAC built in would be very sweet.
Awesome! It\'s more then i can understand. But that makes it more interesting to read ;) Very cool arcade console this way.
Nice work! Might try to wrap a rasteriser around it when I get the chance... :)
Excellent design! You should be able to play Gravitar with a ROM swap if I am not mistaken!!! :-)
Sweet! That theory of operation bit was exactly the sort of kicking-off point that I was looking for. The arcade games\' docs are great at explaining how the deflection amps work given the correct yoke, but not so much when it comes to the underlying design principles. I\'ve got access to a couple of original XY monitors and can compare (out of circuit) characteristics of their \"real\" yoke with a modified and/or hand-rewound ones. Thanks again.
VecTor: You might want to take a look at http://www.instructables.com/answers/convert-any-CRT-TV-or-monitor-into-a-vector-XY-m/ ; I basically used that link and the pages the comments point to as a template for what I did.
Awesome hack! I\'d like to hear a little more about the means by which you figured out how to modify the deflection coils and/or control their behavior (replacing with dummy inductors, cutting out chunks of coil wire, and/or both). There are a lot of CRTs out there collecting dust because their deflection yokes (whether the yoke is high-impedance or low-impedance depends on the design of TV set\'s chassis, but most fall into one or two broad ranges) are optimized for raster scan displays. Figuring out how to drive a suitably-modified raster yoke would be an interesting summer project. (Assumiung the impedance of a vector display\'s deflection coils needs to be about the same on both X and Y coils, and assuming further that the deflection board is being built from scratch, it might be easier to just add an inductor, or even something as simple as a series resistor, to the \"wrong\" coil...)
I love the idea of FPGAs. I have also toyed with the idea of using a vector display. So logically, I was very happy to read this. Great work!
Zapro: The FPGA-board is a 6- or 8-layer one, so the sticker is there to indicate the inner layers have been checked using an X-ray-machine.
Wow, what an amazing build! - What is up with that radiation sticker on the FPGA-board ? ;-)
Extremely impressive. My VHDL skills are... non-existent. Hey, though, be careful with those CRTs. Basically it\'s a high-power electron gun, capable of producing some pretty DNA-melting x-rays. Don\'t run it with the magnets off :-p
Very nice Sprite_tm :) Looking forward to more Atari Vector stuff here ^^
Tip for the woodworking: Take some wood \'dust\'. Add a tiny amount of wood-glue to it, to make a very thick paste. This gives you an good (and eco friendly) filler, instead of the (crappy) white. About the hardware, it\'s an very nice (hacky) implementation. My compliments!
Made good on my threat (3 years ago) to rasterise it! ;) <http://ngpace.blogspot.com/2015/11/like-riding-bicycle.html>