Getting SPI on a router


Cheap routers such a s the TP-LINK 703n and the TP-LINK MR3020 (seen above) can be used for much more than just connecting your laptop to your cable modem. They’re actually very small Linux boxes and with OpenWRT, you can control every aspect of these tiny pocket-sized computers. It’s frequently been suggested that these routers are awesome substitutes for the usual methods of getting Internet on a microcontroller, but how do you actually do that? The onboard serial port is a great start, but this also dumps output from the Linux console. What you need here is an SPI connection, and [ramcoderdude] has just the solution for you.

Linux already has a few SPI modules, but these are only accessible with kernel drivers. Traditionally, the only way to access SPI is to recompile the kernel, but [coderdude] created a kernel module that allows any device running the Attitude Adjustment OpenWRT image to dynamically allocate SPI busses.

He’s already submitted this patch to the OpenWRT devs, and hopefully it will be included in future updates. Very cool, we think, and something that can open a whole lot of doors for hacking up routers very easily.

SenseLamp automates rooms by replacing light fixtures


Would you believe that this beautiful light fixture is actually a hacked together home automation project? Okay, so this wire mess is the second of three versions that [Christian] built. It replaces a light fixture in the room, but if you look closely you’ll see that there is a compact fluorescent bulb included in the build. The laser-cut frame acts as a bit of a lamp shade, while providing a place to mount the rest of the hardware.

The final version cleans things up a bit, and adds a footprint for the PIR motion sensor that he forgot to design into this version. The idea is that each lamp monitors motion in the room, switching the light on and off again as necessary. A light-dependent resistor ensures that the bulb is only powered up if the room is dark so as not to waste electricity during the day.

The build includes a sensor package that reports back temperature and humidity data. Communications are provided by a WR703N router rolled into each of the four units installed in his house. With this kind of hardware at his disposal it should be a snap to control every IR remote control device in his house via the network by adding an IR LED and some code to the lamps.

Turning a tiny router into a webradio


While the hacking zeitgeist is focused nearly entirely on all those new ARM dev boards that include the Raspberry Pi, some people out there are still doing it old school by modifying existing electronics to suit their needs. [Peter] picked up one of those very inexpensive TP-Link 703n wireless routers we’ve seen before and modified it into a standalone web radio, complete with volume and tuner knobs.

The TP-Link 703n is a wireless router smaller than a credit card available from the usual Chinese resellers for about $20. Able to run OpenWRT, this very inexpensive piece of hardware can be transformed into a device comparable to the Raspberry Pi; a complete Linux system with a few GPIO pins.

[Peter] took his 703n router and added an ATtiny85 connected to two pots and the internal UART. This, along with a script to read the values from the pots, tells the router what station to tune into and what volume to play it. The audio is handled by a USB soundcard with an internal speaker, making [Peter]‘s build one of the smallest purpose-built Internet radios we’ve seen.

You can see [Peter]‘s radio in action after the break.

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