$3 DIY game console

June 14, 2010 9:36 AM

RBox: A $3 DIY video game console.

The parts for this homebrew video game console cost about $3 total. The demo video at the start of the post illustrates the device's video and audio output. The source code hasn't been posted yet (it looks like the creator intended to include it, but forgot to do so), but the schematics appear at the end of the post, and there is tons of nerdtastic detail along the way. Downside: so far this console has no games.

posted by twirlip (21 comments total)

This looks like a fun project. Although once the technology gets perfected, I expect Chinese-made versions to be sold in miniature Wii/360/PS3 cases outside of every bootleg-goods store.

Relevant Onion Article: Broke Dad Makes Son PlayStation 2 For Christmas
posted by griphus at 9:43 AM on June 14, 2010

This same guy also build the astounding iPhone "killer" and this sweet wikireader, both of which are also ridiculously cheap and underpowered for what they do.

I'm sure writing code for platforms like this must cost a lot more than $3 (even /hr) in frustration and needing-to-be-super-clever.
posted by DU at 9:43 AM on June 14, 2010

[removed direct schematics link, it doesn't work w/o already being on the site. carry on.]
posted by jessamyn at 9:49 AM on June 14, 2010

This guy is the cat's pajamas. Every week or so someone on Hackaday posts a new game console they make with parts, solder, and tears.

See also the black art of game console design.
posted by hellojed at 9:59 AM on June 14, 2010 [1 favorite]

but can it run doom?
posted by shmegegge at 10:01 AM on June 14, 2010

None of the things I've read since 1980 about computer graphics and television technology allow me to accept this. What is happening here? Where is the 3D calculated? Are these graphics really being created by individual scanlines on the fly?

Everything I thought I knew says you couldn't do this without a crapload of bitmap memory or a sprite handler or the specialized chips in the Amiga. When I look at this thing, I feel like the chimp in that magician video. I know I should be able to understand how this thing generates such awesome video, but somehow I have a lot of holes in the things I managed to learn at age 7.
posted by scrowdid at 10:02 AM on June 14, 2010 [1 favorite]

I'm not sure it's worth imagining a Beowulf cluster of these.
posted by WinnipegDragon at 10:09 AM on June 14, 2010 [1 favorite]

If you're interested in things like this, you might want to check out El Jugador, a low priced retro gaming platform with controller ports.

I like the minimalist simplicity of the RBox, but if I were going to spend time with some hobby programming, I would go with the Propeller platform. Of course, I'm a software guy, not a hardware guy.
posted by demiurge at 10:19 AM on June 14, 2010

oh the source code looks very interesting
i sure wish i would have attended my c++ classes more frequently
posted by scrowdid at 10:22 AM on June 14, 2010

The source code.
posted by twirlip at 10:26 AM on June 14, 2010

What facinates me is that this doesn't use a video chip or any video hardware at all. Instead the CPU generates the video signal on the fly!

That's pretty amazing, IMO.
posted by delmoi at 10:29 AM on June 14, 2010

Oh wow, it's not even using a frame buffer. that's insane.
posted by delmoi at 10:33 AM on June 14, 2010

Everything I thought I knew says you couldn't do this without a crapload of bitmap memory or a sprite handler or the specialized chips in the Amiga.

Software is doing the signal generation. No different then doing audio in software instead of doing a sound chip. Just More's law in practice.
posted by delmoi at 10:34 AM on June 14, 2010

It's a 2600 on steroids where the steroids are used to drop all the support circuitry. Yes, you don't need a framebuffer although it makes like a heck of a lot harder and you end up having very tight timing constraints. Framebuffers allow you to decouple thing and techniques like double-buffering allow you to take your sweet time drawing frames. No such luck here.

It's an interesting retro-computing project that demonstrates a huge advance in terms of price instead of functionality but I'm not sure it's important versus side-show levels interesting.

As for video I don't quite get how he does it - he has some gpio lines for one signal and the other comes from... more gpio lines? the memory bus? I can't quite parse what he wrote.
posted by GuyZero at 10:41 AM on June 14, 2010

he has some gpio lines for one signal and the other comes from... more gpio lines?

Luma from a bunch of GPIOs.

Chroma from an SPI output from the microcontroller. SPI is basically an 8-bit clocked serial interface. And his microcontroller has a FIFO on its SPI. So from software, he can write 16 bytes of data = 128 bits of data to the SPI FIFO; and the microcontroller will autonomously clock that out onto his chroma line at whatever rate it has been configured at.
posted by We had a deal, Kyle at 11:28 AM on June 14, 2010 [1 favorite]

Thanks! I couldn't figure out what the SPI interface was. Too bad the CPU didn't have onboard DACs then he wouldn't have needed anything.
posted by GuyZero at 11:42 AM on June 14, 2010

Chroma from an SPI output from the microcontroller. SPI is basically an 8-bit clocked serial interface. And his microcontroller has a FIFO on its SPI. So from software, he can write 16 bytes of data = 128 bits of data to the SPI FIFO; and the microcontroller will autonomously clock that out onto his chroma line at whatever rate it has been configured at.

Having generated a video signal from a microprocessor before, I have to say that's pretty boss. Wish I'd thought of it.
posted by heathkit at 11:42 AM on June 14, 2010

Wow, y'all folks, I played a "Playing Station number 3" last weekend and it was really amazing. I played something called "The Metallic Gear Episode 4: Patriotism" and it was a lot of fun. What's with all these numbers huh? Videogaming is fun!

Does anyone know how to port RPGmaker2003 games to RBox?
posted by fuq at 8:18 PM on June 14, 2010

I'm sure writing code for platforms like this must cost a lot more than $3 (even /hr) in frustration and needing-to-be-super-clever.

That is so not the point it isn't even funny.
posted by The Devil Tesla at 9:12 PM on June 14, 2010

scrowdid: The secret is that instead of having, say, a processor running at 7 MHz that takes up to 70-odd cycles to do a multiply, you have a processor running at 52 MHz that can do single-cycle multiplies.
posted by hattifattener at 10:59 PM on June 14, 2010

The old Sinclair ZX81 (my first computer) did similar "clever" tricks to keep costs down.

These days though, I think it'd be worth it to spend another $3 on a second microcontroller just to handle the display stuff.
posted by suetanvil at 7:31 AM on June 15, 2010