Great Scott! A Flux Capacitor Notification Light

If you are into your social media, then you probably like to stay updated with your notifications. [Gamaral] feels this way but he wasn’t happy with the standard way of checking the website or waiting for his phone to alert him. He wanted something a little more flashy. Something like a flux capacitor notification light. This device won’t send his messages back in time, but it does look cool.

He started with an off-the-shelf flux capacitor USB charger. Normally this device just looks cool when charging your USB devices. [Gamaral] wanted to give himself more control of it. He started by opening up the case and replacing a single surface mount resistor. The replacement component is actually a 3.3V regulator that happens to be a similar form factor as the original resistor. This regulator can now provide steady power to the device itself, as well as a ESP8266 module.

The ESP8266 module has built-in WiFi capabilities for a low price. The board itself is also quite small, making it suitable for this project. [Gamaral] used just two GPIO pins. The first one toggles the flux circuit on and off, and the second keeps track of the current state of the circuit. To actually trigger the change, [gamaral] just connects to the module via TCP and issues a “TIME CIRCUIT ON/OFF” command. The simplicity makes the unit more versatile because an application running on a PC can actually track various social media and flash the unit accordingly.

Mesh networking with multiple Raspberry Pi boards

Since he’s got several Raspberry Pi boards on hand [Eric Erfanian] decided to see what he could pull off using the robust networking tools present in every Linux installation. His four-part series takes you from loading an image on the SD cards to building a mesh network from RPi boards and WiFi dongles. He didn’t include a list of links to each article in his post. If you’re interested in all four parts we’ve listed them after the break.

He says that getting the mesh network up and running is easiest if none of the boards are using an Ethernet connection. He used the Babel package to handle the adhoc routing since no device is really in charge of the network. Each of the boards has a unique IP manually assigned to it before joining. All of this work is done in part 3 of the guide. The link above takes you to part 4 in which [Eric] adds an Internet bridge using one of the RPi boards which shares the connection with the rest of the mesh network.

If the power of this type of networking is of interest you should check out this home automation system that takes advantage of it.

Continue reading “Mesh networking with multiple Raspberry Pi boards”

IP over LEGO train carrier

[Maximilien] sent in a networking protocol built out of a LEGO train set. Unlike IP over Avian Carrier this system won’t be killed by plate-glass windows or birds of prey, but we’d hate to step on [Max]’s work in bare feet.

The system uses a USB flash drive to carry data around to different nodes. At each node, [Max] removed the power from the tracks and added a relay to start the train up again. A mechanical switch detects the presence of the train, and an Arduino makes the link to the Linux boxes via serial-over-USB.

The physical connection of the flash drive is with four wires and aluminum foil contacts. To send data, the system waits for the train to arrive at the ‘station’, mounts the drive, checks if there is data for it, and sends what needs to be sent. After unmounting the drive, power is applied to the local rail and the train continues on its journey.

[Max] admits that the latency on his network is terrible, but the bandwidth should be fairly good. As the old saying goes, ‘Never underestimate the bandwidth of a station wagon full of tapes.’ We’re not quite sure how that applies to LEGO trains, but there you go. Check out the gallery of [Max]’s work after the break.

Continue reading “IP over LEGO train carrier”

Nanode: A low-cost network-enabled Arduino Ethernet alternative


The folks over at Hackspace London have been working hard to create a “very low cost, open source, Internet connected platform on which others can develop their ideas”, which they have dubbed “Nanode”.

Essentially an Arduino with Ethernet networking on-board, the Nanode is armed with an ATMega 328 microcontroller along with all the other standard goodies you would expect from an Arduino-compatible device. The Nanode can be controlled with a web browser right out of the box, thanks to some custom Ethernet libraries. Additionally network of Nanodes can be easily configured to communicate with a “master” unit via a multidrop serial bus, allowing the device to be used for a wide array of distributed control tasks.

Obviously most of these features can be had in the form of an Arduino Ethernet board, or achieved by using an Ethernet shield. The Nanode is a touch cheaper than either option at $40 for a kit, and the native networking capabilities sound like they would be quite handy. That said, we are a bit bummed that it only has 10BaseT networking capabilities, though it is always nice to have options when it comes to choosing a microcontroller board.

[Thanks, TheHypnotist]