[youtube=http://www.youtube.com/watch?v=yDA16dfqgeg]
It might be a little bit of overkill, but this etching container agitator sure looks convenient. There’s not much to it technically, a small circuit with an ATtiny45. For those beginning with this stuff, he has written a pretty good tutorial on working with basic microcontrollers. If you are more interested in a tutorial on etching, we did a guide on how to etch a single sided PCB.
We’ve seen our fair share of AVR projects, but this one’s pretty cool. AVGA is a color video game development platform based on the Atmel AVR family of microcontrollers. As seen in the picture above, one of the AVRs that the project uses is the popular ATMega168. There were several technical hurdles to using the AVRs to run color video games; one of the most difficult problems was figuring out a way to display detailed graphics from AVRs limited onboard RAM. Eventually, the developers figured out a way to display detailed graphics using a TILE-based driver. The TILE driver works by dividing the screen into X and Y coordinates, dividing the graphics into tiles. Then, when a graphic is needed it’s addressed from a reference table that’s stored in the AVR’s onboard RAM, allowing the bitmap graphic to be loaded from a game’s ROM. Currently, the only games available for the platform are a Super Mario clone, a Pacman clone, and a Snake clone. While there are only a few games available, the platform definitely looks promising. If anything, this project serves as a great example for what off the shelf microcontrollers are capable of.
[Sprite_tm] automated a portion of serial hacking by sniffing out the baud rate using an ATtiny2313 and FT232 breakout board. The firmware assumes 8 data bits, no parity, and 1 stop bit (8N1). This is pretty much defacto among serial ports so it should work well, though some devices do use different settings. The auto detection routine can sniff rates as low as 110 baud and supports non standard rates. Released under GPLv3, the software is also supplied in hex format. [Sprite_tm] has provided great project in past such as Working with VFDs, Controllable bristlebot, and AVR boost converter. Additional information regarding serial hacking after the break.
[WaveRider] is using a type of phase shift keying called BPSK to transmit digital sound and video for remote telemetry. Though a higher signal to noise ratio (SNR) is generally sought after with communications, legal limitations are imposed on total radiated power. To balance the two headed beast, he opted out on frequency shift keying due to binary shift keying’s ability to work with lower SNR. This adds the difficulty of properly reconstructing the digital signal at the receiver. A PLL based carrier regeneration circuit is used to reconstruct the signal. Using the Rabit2000 processor as the host controller on both transmitter and receiver, 96KB/Sec serial data is obtained. On the other side of the spectrum is the Homemade regenerative tube radio.
The 1-Wire HVAC monitoring system is for residential Geothermal HVAC systems. This project utilizes the so called 1-wire temperature sensor. A single board computer handles the brunt of the work including web accessible trend data. With access to the underling temperatures, the over all system performance may be gauged. Earlier this year we covered a HVAC web enabled monitor that adds an element of control. As the industry adopts modern control architectures, we hope to see more HVAC hacks around.
[Vince Briel] has created an embedded device based on the Parallax Propeller chip that acts as a serial terminal. It takes input from a standard PS/2 keyboard and outputs color VGA. It also has a second serial port to connect to a PC for debugging or programming. He is selling kits and has the schematics available. The board has a lot of hacking potential and it could easily be made into a video game or a Wikipedia browser.
[via RetroThing]
[Seth King] sent in his latest hack where he used an Arduino to regulate various aspects of a greenhouse. He has sensors for soil and air temperature as well as light and moisture. He built a custom circuit that uses relays to power fans, lights, and heaters. Using timers and the sensor data, the devices can be triggered to create the perfect environment for sprouts. He hopes to make the whole thing wireless by integrating XBees, but for now he ran a USB cord to his computer.
Related: Automatic grow light
