When the RepRap team found themselves pushing the limits of the Arduino, they started looking for alternatives. They found it in the ATMega644P. It has four times the memory and four times the RAM compared to the ATMega168 used in the standard Arduino. It also has 32 I/O pins. They ported the Arduino software to the microcontroller and started producing Sanguino boards. Now that the base design is nailed down, they’ve begun expanding it to their specific purpose. Pictured above is a prototype RepRap motherboard. While the Sanguino is barebones, this board has onboard connectors for all of the RepRap’s motors, so you can just plug it in. It is also designed to support the future Generation 3 electronics. Probably the most interesting feature is the SD card slot. The goal is to eventually have a board that can run the RepRap without a host computer if necessary; it will manufacture designs directly from the flash card.
Day: December 24, 2008
Pelican Case Xbox 360
[Ben Heck] has put the final touches on his Pelican case Xbox 360. This prototype was constructed for use by troops stationed overseas. When he announced the project in October, he already knew some of the hurdles he would face. An industrial Velcro style product is used for all component mounting so the air/water-tight seal of the case remains intact. He sanded the surface so that it would stick better. [Ben] mentions that he ended up using less Velcro than he planned on because it held so well. Not being able to cut the case meant the DVD drive had to be converted to top-loading. The tray movement limit switches have been relocated so they now respond to lid position. He regrets not being able to motorize the lid, but let it go since this is still just the first attempt. Extra copper was added to all of the heat sinks to improve cooling. This Xbox is for sale and he’d love to hear from anyone that wants to put it into production. The write-up has a ton of pictures and you can see a video of it below.
Giant LED Lamp
[guyfrom7up] must really really love LEDs. When he needed some lighting, which would obviously be LED powered, he chose to actually build a giant LED. Well, he didn’t actually build a giant functional LED, but rather an LED shaped diffuser for some high powered LEDs. He takes us through the process of first creating a wooden model, using that to create a mold, then forming the final diffuser. The final product is very well done, and instantly identifiable by any geek.
[thanks Brian]
Multitouch MAME Cabinet
[rdagger] sent us this really well done multitouch MAME cabinet build. He ha penned to find a used, and fairly worn cocktail cabinet. The monitor was damaged, keys lost, and internals had been home to mice for some time. He promptly tore out the old guts, replaced the smelly mouse damaged base and began building the projection system. For touch sensing, he’s using a web cam with the IR filter removed to detect disturbances in some IR laser beams. We’re not completely clear on how he mounted the lasers, he skips over that part. There’s nothing groundbreaking in the technology here, we’ve done multitouch many times before. This project stands out in its execution. [rdagger] has done a fantastic job, the construction looks fantastic. Check out a video of it working after the break.
Parts: 1K 1-Wire EEPROM (DS2431)
The Maxim DS2431 1K EEPROM is 1-Wire device that adds storage to a project using a single microcontroller pin. We previously interfaced a 1-wire thermometer, but this EEPROM is slightly different because it draws power directly from the 1-Wire bus. Grab the datasheet (PDF) and follow along while we read and write this simple 1-Wire memory.