Linux On A Nspire CAS CX Calculator

November 12, 2012 by Eric Evenchick 35 Comments

It’s great to see Linux running on a device in a way that was never intended. [tangrs] has successfully run a Linux kernel on the ARM based Nspire CAS CX graphing calculator. He’s developed an in-place bootloader that allows a kernel to be loaded from within the stock Nspire OS. It also allows for peeking and poking at memory for debugging.

[tangrs] also managed to get USB host mode working on the calculator. This allows for a USB keyboard and Wifi dongle to be connected. At this point, the calculator can connect to the internet and browse using a text-based browser: Links. The calculator runs a SSH server for remote access, and graphical browsing is in the works.

It looks like this calculator is on the way to being a handheld Linux device. All of the source for the kernel and bootloader are available on [tangrs]’s Github and updates on his blog. After the break, check out a video of text-based browsing using a full keyboard.

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Lucky Cat Hit Counter

November 11, 2012 by Eric Evenchick 17 Comments

[Jan] was looking for a way to monitor web site hits while sitting on the couch. This lead to the Lucky Cat Hit Counter. The hack gives a stock Lucky Cat some new hardware: a servo, a RGB led, a light sensor, and a 7 segment display. The added components are controlled by an Arduino Ethernet.

The Arduino Ethernet is set up as a web server. When a visitor fetches [Jan]’s site, a GIF is requested from the Arduino. This trigger changes the RGB LED color, increments the seven segment display, and of course, makes the cat wave by actuating the servo. The light sensor is used to make the cat silent at night. When the light value is below a threshold, night mode is engaged and the cat doesn’t wave.

After the break is a video walk through of the Lucky Cat receiving some HTTP requests.

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Upverter 2.0 Launches

November 6, 2012 by Eric Evenchick 41 Comments

Disclosure: I currently work at Upverter

We’ve featured Upverter here in the past. At that time, the EDA tool was capable of collaborative schematic capture. Today, Upverter is launching version 2.0 of their tool which includes many new features allowing for end-to-end electronics design.

Upverter now has a PCB editor, allowing you to manufacture your designs. They are working with PCB manufacturers to make it easy to choose a fab and submit design files. Other new features include a Spice based simulation engine allowing in-browser simulation, and product lifecycle management features to help manage your project’s bill of materials.

When we last looked at Upverter, it was just a tool for creating and sharing schematics. With today’s launch, the tool can be used for designing electronics from start to finish. Since Upverter is free for open source projects, it will be interesting to see how hackers use it.

You can check out a tour of the new features. Any thoughts on using a cloud based EDA tool? Let us know in the comments.

Thinking Cap Is Also Party Hat

November 5, 2012 by Eric Evenchick 10 Comments

The Thinking Cap is a piece of wearable signage that lets you display what’s on your mind. The hat uses a Teensy 2.0 connected to a Bluetooth radio to allow the wearer to update the message on the fly, letting the room know what their thinking at that instant.

This hack is based off of LPD8806 controlled LED strips, which are becoming very popular for adding lots of LEDs to anything. There are five strips that need to be controlled over SPI, but the Teensy only has one SPI peripheral.

This lead to the use of multiplexer to allow for controlling each strip individually. The hat uses an interesting and low cost scheme to multiplex five channels using two 744052 dual 4 channel multiplexors and a 7400 inverter.

The Teensy can receive messages using the Bluetooth serial port protocol. The 5 x 7 pixel characters are stored in a framebuffer, and shifted around the hat to create the animation.

The result is a bright message circling around the user’s head, which can be updated with a smartphone over Bluetooth. Check out a video demo of the hat after the break.

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Super Serious Garage Door Opener

October 24, 2012 by Eric Evenchick 17 Comments

Tired of cheap plastic garage door openers? [Yetifrisstlama]’s is probably the most serious garage door opener that we’ve seen. The case is an old emergency stop switch, which has plenty of space for the circuitry and features a big red button.

This build log starts with details on reverse engineering the original door opener’s protocol. It’s an amplitude-shift keying (ASK) signal that sends a 10 bit code to authenticate. The main components inside are a PIC16LF819 microcontroller, a MAX7057 ASK/FSK transmitter, and some RF circuitry needed to filter the signal. There’s a mix of through hole and surface mount components mounted on a prototyping board, requiring some crafty soldering.

[Yetifrisstlama] says that the next step is to add a power amplifier to increase the range. The code and project files are also provided for anyone interested in working with ASK. While the hack looks awesome, it might make bystanders think you’re doing something more sinister than opening a garage door.

Add An Arduino To A Google+ Hangout

October 22, 2012 by Eric Evenchick 3 Comments

Google+ Hangouts provide a group video chat with the ability to add apps. [RobotGrrl] created a Node.js web app to control an Arduino that can be added to a Hangout.

There’s a Javascript client that runs inside of the Hangout and communicates with the Node.js server running on an EC2 server over WebSockets. The server receives this client data and sends commands to Processing using TCP sockets. Processing deals with communicating with the Arduino, allowing you to control many things from the Hangout.

In this simple example, [RobotGrrl] demonstrates how to toggle an LED from the Hangout. This includes a tutorial on setting up your EC2 instance, full source for the server and client apps, the processing sketch to control an Arduino, and the code to allow the app to be added to a Hangout.

This example shows the basics, but there’s a whole slew of things that could be controlled with this system. [RobotGrrl] even demonstrates some robots that are controlled from a Hangout interface.

Check out an overview video after the break.

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Halloween Light Show Gets An Upgrade

October 22, 2012 by Eric Evenchick 6 Comments

This is [Dave]’s second year of putting on a Halloween light show (cache), and his latest production has received some upgrades over last year’s Christmas show. He’s switched from Christmas style bulb lights to high brightness LEDs, and upgraded to 48 channels of control.

The controllers are from Light-O-Rama, and each provides 16 output channels. They communicate over RS-485; the same type of network used for controlling professional theater lights with the DMX512 protocol. The whole thing is powered by a 20 A DC supply from some Chinese retailer.

[Dave]’s show features light up pumpkins, tombstones, and faces mounted on his house. The lights are coordinated to a list of songs that he plays over an FM transmitter, allowing for cars to tune into the music that’s synced up with the lights.

If you happen to be in Estacada, OR, you might want to head over to [Dave]’s and check out the show in person. Otherwise, there’s two videos of the light show after the break.

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