Chatbox Wireless IM Client

April 17, 2011 by Mike Szczys 8 Comments

[Utpal Solanki] wanted to do some text chatting from the comfort of the couch. He built this wireless chat client that he calls Chatbox using a microcontroller, a character LCD screen, and a keypad that he built himself.

The device communicates via an Infrared emitter and receiver. It pairs up with an Arduino using an IR shield that [Utpal] built. The handheld unit flashes a pair of white LEDs whenever it receives a message from the Arduino. You can then hit the Inbox button and scroll through to read what was received. To reply just type on the keypad the same way you would with a cellphone, then hit the send button to shoot that message back to the Arduino.

On the computer side of things the messages are being relayed to and from the Arduino over a USB connection. Early on in the video demonstration (embedded after the break) [Utpal] shows his Chat Box program communicating via the handheld unit in the same way that other messenger programs work.

Looks to us like he’s built his own non-pink version of what the IM-ME was originally intended to do.

Continue reading “Chatbox Wireless IM Client” →

DTMF Shield Aimed At Ham Controlled Arduino

April 17, 2011 by Mike Szczys 8 Comments

[Colin] wanted a way to reliably control an Arduino via ham radio. One of the easiest methods of automated radio control makes use of Dual-Tone Multi-Frequency signalling. To those who aren’t into amatuer radio you probably recognized DTMF as the touch-tone system for telephone communications. [Colin] built a shield that has an audio input and can decode DTMF signals.

The hardware is based around an MT8870 DTMF decoder chip. This is a popular choice for DTMF hardware because it does all of the decoding work for you. Whenever a valid tone is detected it outputs the associated value in binary on four output pins. There is a fifth pin that strobes after each new tone. [Colin’s] design offers a lot of feedback for what’s going on with the input signal. The DTMF value is displayed on a 7-segment display (controlled completely in hardware), the value is output on for Binary Coded Decimal pins, and mapped to a set of ten pins which pull to ground to match the digit received.

Webcam Turned Security Cam With Motion Detected Email Notifications

April 17, 2011 by Mike Szczys 27 Comments

[Sean] used his old webcam to assemble a closed circuit television feed for his home. He already had a server up and running, so this was just a matter of connecting a camera and setting up the software. He wasn’t satisfied by only having a live feed, so he decided to add a few more features to the system.

He started off by hanging a webcam near the front of his house. He mentions that he’s not sure this will last long exposed to the elements, but we think it’d be dead simple to build an enclosure with a resealable container and a nice piece of acrylic as a windows. But we digress…

The camera connects via USB to the server living in the garage. [Sean’s] setup uses Yawcam to create a live feed that can be access from the Internet. The software also includes motion detection capabilities. Since he wanted to have push notifications when there was action within the camera’s view he also set up Growl alert him via his iOS devices. You can see [Sean] demonstrate his completed CCTV system in the video below the fold.

Continue reading “Webcam Turned Security Cam With Motion Detected Email Notifications” →

Hackaday Links: April 16, 2011

April 17, 2011 by Mike Szczys 8 Comments

Induction cook top provides power too

We’re familiar with induction cook tops but we never thought to power a microcontroller with one. [Thanks Hadez]

Ping-Pong Uranium

We’ve been big fans of the chain reaction demonstration using ping-pong balls and mouse traps ever since we saw [Mr. Wizard] do it back in the day. If you don’t know what we’re talking about, check out this demonstration that is analogous of a fission reaction. [Thanks nateL]

Phone tripod enclosure

If you’re interested in using your smart phone for some photography, [Mike] has a nice wood and elastic mount for an iPhone which you might try yourself.

Bicycle snow tires

Admittedly we’re a bit late on this one. But keep it in mind for next year: you can use some zip ties for added traction on your bike when it snows. [Thanks Rob]

Now you can BE mario

A little Kinect script lets this gentleman play Super Mario Bros. with his body. Now you can have all the fun that goes along with being a pixellated character stuck in a two-dimensional environment (plus, there are shrooms). [Thanks Das_Coach via Slashdot]

The Basics Of Building A Multitouch Table

April 16, 2011 by Mike Szczys 15 Comments

Here is a bare-bones multitouch table setup. We looked in on [Seth Sandler’s] multitouch work a few years ago when he completed the MTmini build. He’s scaling up the size a bit with the MTbiggie, and showing you how easy it is to put together. The demo rig seen above is just a couple of chairs, a sheet of acrylic, a mirror, a projector, a computer, and a diy infrared webcam.

The rig uses ambient infrared light to detect the outlines of your fingers when they touch the acrylic surface. A webcam with an exposed camera film filter feeds an image of the infrared light received below the surface to the computer. The incoming video is processed using Community Core Vision, where each individual point is isolated and mapped. Once the data is available the sky’s the limit on what you can develop. [Seth’s] demo packages include a mouse driver, some physics applications, an Angry Birds implementation, and a few others. See for yourself in the video after the break.

Continue reading “The Basics Of Building A Multitouch Table” →

The Origin Of CTRL-ALT-DELETE

April 15, 2011 by Mike Szczys 32 Comments

You may not have ever thought about it, but the far-too-often-used keyboard combination of Control + Alt + Delete had to have been brought into existence by some random coder at some point in technological history. But wait, it wasn’t just a random coder. The keystroke combo is attributed to [David Bradley]. He was one of the original designers of the IBM Personal Computer. You can even hear his own recount of the story in the video after the break.

He came up with the idea after growing weary of waiting for the Power-On Self Test (POST) routine to finish during each reboot of his software testing regiment. We remember the old days of slow hardware and can understand his frustration at the lost time. He decided to throw in a shortcut that allowed the software to reboot without power cycling the hardware. The original implementation used CTRL-ALT-ESC, but was later changed so that one frustrated keyboard mash couldn’t accidentally reboot the system.

Continue reading “The Origin Of CTRL-ALT-DELETE” →

HsNet: Node Communications For Feature-limited Microcontrollers

April 15, 2011 by Mike Szczys 11 Comments

[Diego Spinola] wrote in to tell us about a node communication system he’s been working on called HsNet. The aim is to build a system of nodes that can be made up of small and inexpensive microcontrollers. The problem is that the least expensive controllers often don’t have a hardware UART. HsNet implements the RS485 protocol using a software UART along with a slim and sleek addressing scheme.

The first module developed, seen in the image above and video after the break, is a single channel pulse-width-modulation node using a PIC 12F683. It can be sent commands in the payload of the HsNet packet format. The PWM modules accept three different commands; one is a desired PWM value, another is a delay between steps for the PWM, and the last toggles a blink function.

He has also developed an analog sensor module and an Arduino-based TCP/IC gateway module. Now that the packet communications have been established, it will be rather simple to add nodes based on that groundwork. [Diego] brought these components together to build an interactive wall which can also be seen after the break.

Continue reading “HsNet: Node Communications For Feature-limited Microcontrollers” →