Driving 1000 NeoPixels With 1k Of Arduino RAM

timing

NeoPixels, or WS2812 RGB LEDs, are the display device du jour for impressive and blinding lighting projects. Commonly known for very tight timing requirements, [Josh] discovered this is, in fact, usually unnecessary. The timing requirements for NeoPixels aren’t as bad as they seem, once you get to know them.

The official WS2812 timing specs give values that are fairly constraining for anyone writing a library to drive these RGB LED pixels, but simplifying the timing diagram by assuming a 50% duty cycle on the data lines and ignoring the longer maximum times results in a surprising conclusion: the only tight timing parameter for NeoPixel signaling is the maximum width of the 0-bit pulse.

Realizing this, [Josh] wrote a simple demo program to drive over 1000 NeoPixels – an 11 meter long strip – using 1K of RAM on an Arduino. The trick comes by simply delaying the bitbanging a set number of cycles. No obtuse assembly required.

There is only one problem with [Josh]‘s method of driving a nearly unlimited amount of NeoPixels – building a display where every NeoPixel is an element in a larger image, such as in a video display, is impossible on systems with limited amounts of RAM. The code writes values to the NeoPixel strip algorithmically, so if you can’t build your animation with for loops, you’re out of luck. Still, Driving this many NeoPixels is a migraine trigger, and we have to give [Josh] credit for doing this with 1K of RAM.

Check out the video of [Josh]‘s extreme NeoPixel strip below.

[Read more...]

Introducing The Arduino Zero

Zero

The Arduino Uno is the old standby of the Arduino world, with the Arduino Due picking up where the Mega left off. The Arduino Tre is a pretty cool piece of kit combining a Linux system with the Arduino pinout. Care to take a guess at what the next Arduino board will be called? The Arduino Zero, obviously.

The Arduino Zero uses an Atmel ARM Cortex-M0+ for 256kB of Flash and 32k of RAM. The board supports Atmel’s Embedded Debugger, finally giving the smaller Arduino boards debugging support.

The chip powering the Zero features six communications modules, configurable as a UART, I2C, or SPI. USB device and host are also implemented on the chip, but there’s no word in the official word if USB host will be available. There are two USB connectors on the board, though.

The Arduino folk will be demoing the Zero at the Bay Area Maker Faire this weekend. Hackaday will have boots on the ground there, so we’ll try to get a more detailed report including pricing and availability then.

Upgrade Your Garage Door with Arduino and RFID

RFID Garage Door Opener

[Jason] really wanted to build an RFID controlled garage door opener and decided to turn to Arduino to get the job done. For someone who’s never worked with an Arduino before, he really seemed to know what he was doing.

The Arduino acts as the brains of the operation while an off-the-shelf NFC/RFID reader module is used to read the RFID tags. To add new keys to the system, [Jason] simply swipes his “master” RFID key. An indicator LED lights up and a piezo speaker beeps, letting you know that the system is ready to read a new key. Once the new key is read, the address is stored on an EEPROM. From that point forward the new key is permitted to activate the system.

Whenever a valid key is swiped, the Arduino triggers a relay which can then be used to control just about anything. In this case, [Jason] plans to use it to control his garage door. The system also has a few manual controls. First is the reset button. If this button is held down for two seconds, all of the keys from the EEPROM are erased. This button would obviously only be available to people who are already inside the garage. There is also a DIP switch that allows the user to select how long the relay circuit should remain open. This is configurable in increments of 100ms.

For now the circuit is wired up on a couple of breadboards, but it might be a good idea to use something more permanent. [Jason] could always take it a step further and learn to etch his own PCB’s. Or he could even design a board in Eagle CAD and order a real printed board. Don’t miss the video description of the RFID system below. [Read more...]

Reading 2.4GHz Transmitters With An Arduino

QuadThere are a lot of cheap quadcopter kits out there, sold ready to fly with a transmitter and battery for right around $50 USD. One of the more popular of these micro quads is the V2X2 series. They are, unfortunately not compatible with any other radio protocol out there, but [Alexandre] has managed to use the transmitter included with his V202 quad to send data to an Arduino.

Like most quads, the transmitter that came with [Alexandre]‘s V202 operates on 2.4GHz. Listening in on that band required a little bit of hardware, in this case a nordic Semiconductors nRF24L01p. Attached to this chip is a regular ‘ol Arduino running a bit of code that includes [Alexandre]‘s V202 library.

Right now, the build can detect if the quad is bound or not, and read the current position of the throttle, yaw, pitch, and roll, as well as all the associated trims. It’s just the beginnings of [Alexandre]‘s project, but his eventual goal is to build an Arduino bot based on the code, complete with RC servos. Not bad for a transmitter that will be utterly useless when the microquad eventually breaks.

[Read more...]

Barduino, Now With Facebook Integration

Bar

We’ve seen BarBots that will automagically pour you a drink, but how about one with RFID? How about one with Facebook integration, so your friends know how much of a lush you are? Wait. Facebook already tells them that. Huh.

[Andy] and [Daniel]‘s latest build follows on the heels of a lot of similar cocktail bots; an Arduino controls a few solenoid valves connected to a CO2 supply and a few bottles of liquor and mixers that allow drinks to be dispensed at the push of the button. Where this project gets interesting is its use of RFID and Facebook.

The user interface was coded for Windows 7, with an RFID tag (ostensibly issued to each guest) allowing a unique login that checks an SQL server to see what privileges the user has. The app pulls the user’s Facebook profile photo down and displays it in the corner of the screen, and with the server keeping track of how many drinks (and of what kind) they had, with the right permissions it should be possible to post that info to their wall. Because we all know what you did last night, even if you don’t.

DIY Arduino Cases You Never Knew Existed

 

folding arduino lab
There are sure a lot of varieties of Arduinos out there but there may even be more of a variety when it comes to Arduino Cases. Let’s take the most popular Arduino form factor, the Uno. Below are a handful of unique cases for the Uno-sized boards.

 

by [Megaduty], Arduino Protection Box beefy arduino case

We’ll call this one robust. Although it is 3D printed, its intent is to be extremely protective of the inhabitant. Some extra thought went into this case, no tools are needed! After the Arduino snaps into place, so does the cover. There is an access door to get the input/output wires to the free world. [Megaduty] suggests that this contains $0.10 of plastic. Not a bad deal.

 

[Read more...]

uMotio: An Arduino Compatible 3D Gesture Controller

uMotio

The Mooltipass project USB code contributor [Tom] and his friend [Ignatius] recently launched their Indiegogo campaign: meet the 3D gesture controller uMotio (Indiegogo link). As [Tom] has been spending much of his personal time helping the Mooltipass community, we figured that a nice way to thank him would be to try making their great open project one step closer to a disseminated product.

As you can see in the video embedded after the break, the uMotio is a plug and play system (detected as a USB HID joystick & keyboard with a CDC port) that can be used in many different scenarios: gaming, computer control, domotics, music, etc… The platform is based around an ATMega32u4 and the much discussed MGC3130 3D tracking and gesture controller. This allows a 0 to 15cm detection range with a resolution of up to 150dpi. uMotio is Arduino compatible so adapting it to your particular project can be done in no time especially using its dedicated expansion header and libraries. The uMotio blue even integrates an internal Li-ion battery and a Bluetooth Low Energy module.

[Read more...]

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