DDR-5? DDR-4, We Hardly Knew Ye

January 29, 2020 by Al Williams 32 Comments

This month’s CES saw the introduction of max speed DDR5 memory from SK Hynix. Micron and other vendors are also reportedly sampling similar devices. You can’t get them through normal channels yet, but since you also can’t get motherboards that take them, that’s not a big problem. We hear Intel’s Xeon Sapphire Rapids will be among the first boards to take advantage of the new technology. But that begs the question: what is it?

SDRAM Basics

Broadly speaking, there are two primary contenders for a system that needs RAM memory: static and dynamic. There are newer technologies like FeRAM and MRAM, but the classic choice is between static and dynamic. Static RAM is really just a bunch of flip flops, one for each bit. That’s easy because you set it and forget it. Then later you read it. It can also be very fast. The problem is a flip flop usually takes at least four transistors, and often as many as six, so there’s only so many of them you can pack into a certain area. Power consumption is often high, too, although modern devices can do pretty well.

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Walter Is The Slickest Retro-Futuristic Robot Arm

March 9, 2017 by Elliot Williams 11 Comments

[Jochen Alt] is on a roll. We just covered his ball-balancing robot, Paul, only to find his phenomenal six-DOF robot arm in full retro style. Its name is “Walter” and it’s done up in DDR style (the former East Germany), in painted, 3D-printed plastic. The full design and build documents are an absolutely amazing resource if you’re into robot arm or legs.

In particular, the sections on trajectory planning and kinematics are fantastic. If you’re interested in robot motion planning by Bezier curves, you know where to go. (We’ve always wanted a Bezier-curve 3D printer slicer, but that’s another story.) The construction is also top-notch here, and the attention to detail that went into this arm is phenomenal. It’s all done with stepper motors and geared belts, which allow each of Walter’s joints to be driven by a motor that’s one joint further upstream than would be the case if it were designed with servos. [Jochen] even went so far as to expose the belt in some places to show off the gearing. Walter is worth checking out.

Even if you’ll never build such a fancy robot arm, you should read through the docs just to appreciate all of the thought and work that went into this very refined and simple-from-the-outside design. If you’d like to start out on the simple side of the spectrum, check out these robot arms made of office supplies or a desk lamp. Once you’re ready for your second arm project this short list, some of which [Jochen] mention in his writeup, should get you up and grasping. And do check out his balancing bot, Paul.

Hardsync – DDR Reimagined For The C64

November 9, 2012 by Jeremy Cook 10 Comments

For those of you that like to play dance games, but [DDR] for the [PS2] uses too modern hardware for your tastes, [Hardsync] may be for you. Although the chiptune-style music coming out of the [C64] may not appeal to everyone, one would have to imagine that a game like this could have been a huge hit 30 years ago.

As for the hardware itself, it does indeed use one PS2 element, the dance mat. It’s hooked into one of the C64 joystick ports. In this case, the cable was cut, but it would also be possible to make a non-destructive adapter for it so as not to interfere with any future PS2 fun.

The program is made so that fellow retro-dancers can make their own songs. Each song is a discreet file, and can be reconfigured to your own personal mix. Be sure to check out the video after the break of this old-school dance machine in use after the break! Continue reading “Hardsync – DDR Reimagined For The C64” →

[Alex] Shows Us What Happens When Dance Dance Revolution Meets Simon

January 8, 2012 by Mike Nathan 5 Comments

ddr-simon

[Alex] was digging through his closet and came upon an old PS2 game pad for Dance Dance Revolution. He hated the idea of throwing it out just slightly more than the idea of playing DDR again, so he decided to find a way to reuse it.

He was a big fan of the game Simon (aka Genius) as a kid and thought that the DDR pad would make a novel interface for the classic game. Using the PS2XLib by [Bill Porter], which allows an Arduino to easily communicate with a PS2 controller, [Alex] put his Simon replica together in no time flat.

He painted an empty ice cream container with the classic Simon colors, installing a small LED under each quadrant, then wrote the game’s code.

As you can see in the video below, his version of the game works nicely, and forces you to actually get up and move a bit, which we like.

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Large Scale Tetris Game Controlled With DDR Pads

September 23, 2011 by Mike Nathan 5 Comments

led_tetris_using_ddr_pads

Even though Tetris came to the US 25 long years ago, it never fails to entertain. Whatever it is that gives the game such lasting power is a mystery to us, but we’re always interested in seeing fresh takes on the classic game.

MIT students [Leah Alpert] and [Russell Cohen] tweaked Tetris a bit to get players off the couch and literally thinking on their feet. The game boards were constructed using RGB LEDs installed in laser-cut acrylic tubes, arranged in a pair of large 6 foot tall floor standing matrices.

Game play progresses as you would expect, with two players battling head to head to achieve the high score, while simultaneously sabotaging their opponent. Instead of controllers however, each player stands on a Dance Dance Revolution mat, manipulating their game pieces with their feet.

While the DDR pads aren’t exactly a Kinect controller, we have no doubt that playing Tetris this way is incredibly fun – we would certainly install a pair of these boards in our game room without a second thought.

Thanks to everyone who sent this in!

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Building Capacitive Sensitive Floor Tiles

November 22, 2009 by Mike Szczys 38 Comments

That title’s a mouthful but you’re already familiar with the technology and application of foot pads as sensors in games like Dance Dance Revolution. The usbddr project sought to make a USB connected DDR controller from scratch. The microcontroller used is an Atmel ATmega8 running the V-USB firmware for connectivity and uses the analog to digital converts to read in data from the capacitive sensors.

The physical implementation is cleaver. The base plate has a capacitor plate attached to the top of it and the tile has the other capacitor plate attached to the bottom of it. The two are separated by some weather-stripping which is spongy enough to allow compression, bringing the two capacitor plates together.

We’re not convinced of the long-term durability of the system. We certainly don’t think it will hold up to very much hard-core DDR playing. But we would love to see a Super Mario RPG style puzzle to unlock the door to the ‘castle’ at a child’s birthday party.

[Thanks Hans]