A few years ago when I first decided to get my feet wet I got one of those "ELEGO" "all the parts you'll ever need" kits from Amazon. Ever since then my breadboard projects have been powered either by a jumper wire from Blue April's backplane, or by one of these little guys:
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It runs off of a 9V wall wart and is jumper configurable for 3.3v or for 5v. It's OK - but it is kind of a pain, in that it lifts off the board at random times, and it also takes up quite a bit of board space. Around the same time I got that "ELEGO" kit, I got a Jameco breadboard, because they're supposed to be very nice. Well, they are, but sadly the little power doohickey pictured above won't fit on the Jameco power rails. So ever since then I've used a BusBoard breadboard (which is also pretty good) and the nice Jameco breadboard stayed in the box.
On a luthiery forum I sometimes read, one of the contemporary master luthiers says "it's a poor workman who blames his tools... because a good workman doesn't have bad tools!" So in that spirit I decided to upgrade my breadboard situation before returning to my video timing project. I got the cheapest aluminum backed breadboard I could find ($20 on Amazon), switched out its low quality Chinese breadboard with my nice Jameco one, upgraded its extremely flimsy banana jacks with some nicer ones (I also had to give it taller legs to make room for the new nice banana jacks!) and got a 5v switching wall wart for it.
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It seems that generating video timings from a ROM is well-trodden territory around here. As I started building, I discovered that George (gfoot) from right here on the 6502 forums had already done what I had in mind, and much more! I basically ended up duplicating cleanroom-style his "Simplest VGA circuit"
https://hackaday.io/project/175434-worl ... ga-circuit. Mine's not quite identical, but it is close. Also, I ran into a few small problems and gave up the cleanroom idea and asked George some questions. Thanks for your help George!
I kind of like this slow-mo version (Slowest Video Card in the World?) with a bunch of LEDs I made for troubleshooting. The PCB on the left is a debounced button circuit for manually pulsing the clock. The spare breadboard on the right has a 555 timer circuit with a variable resistor so I can run it in bullet time, more or less.
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But, it's only useful if it actually produces correct timings:
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Here's the HSYNC signal at .05 uS x10 per division:
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I think that's pretty good, especially given the length of the ground lead I had to use to get at the signal! I couldn't get my scope to trigger on VSYNC; I guess 60Hz is just too slow for it. Of course, the real question is not whether or not I think it's good, but whether a real monitor will accept it:
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I have to admit that, even though I'm reinventing the wheel here, at this point I did a very undignified happy dance.