Getting SPI on a router

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.

Briefcase mill

briefcase-mill

Take the machine shop with you; that’s the mantra which drove [Ryan] to build this CNC mill in a briefcase. That album will give you a taste of the final product. But you’ll want to dig through two pages of his forum thread starting with this post in order to behold the build process.

The image above is only part way through the fabrication, but we thought it gave the best overall view of his work. It’s missing the cables which connect to the control circuitry in the lid. The bed has also not been installed and this was before he fabricated the protective case for the PCBs.

Getting everything to fit inside of a folding case was quite a trick. Of course he used CAD to make sure it was possible. There are several places where the clearance when closed is about 2mm. We’re shocked by the build quality of the mill itself. It’s a novel idea to make it portable, but the accuracy and reliability of the machine didn’t suffer for the concept.

If you need a desktop mill that’s not quite as portable here’s a project which will dish out some inspiration.

ShapeOko build log — it’s a CNC mill in a box

shapeoko-build-log

We’re not blatantly trying to promo this product. It’s just that the build log covering a ShapeOko assembly process taken on by [Anool] is like crack for those of us who have yet to acquire our own desktop CNC mills.

Like the title says, this thing is basically a mill in a box. But [Anool] decided to order the version of the kit that doesn’t come with any motors or control electronics. He also planned for future upgrades by ordering additional extruded rail to increase the size of the ShapeOko. After assembling the frame his decision to source stepper motors locally bit him as they were out of stock. But there was still plenty to do preparing control electronics during the wait. He based his system on a Raspberry Pi which talks to an Arduino to address the motors and monitor the sensors.

Once all the parts were finally accounted for he tested the rig as a pen plotter. The pen was eventually replaced with the router motor and that ring light PCB seen above was the first thing he milled with it.

[Thanks Justin]

Console radio given new life with a WiFi router retrofit

tube-radio-wifi-router-retrofit

[Craig] did a great job of restoring the case of his antique console radio. But he wanted to bring the guts up to modern standards. The fix ended up being rather easy when it comes to hardware. He based his internet radio retrofit around a wireless router.

We laughed when we heard that he removed about eighty pounds of original electronics from this beast. He then cut a piece of MDF to serve as a mounting platform for the replacement hardware. The WiFi router takes care of audio playback from several sources and offers him the ability to control the stereo from a smart phone or a computer. It has a USB port to which he connected a hub to make room for the USB sound card and a thumb drive which holds his music library. The black box in the upper right is an amp which feeds the NHT stereo speakers housed in the lower half of the cabinet.

It doesn’t make use of the original knobs like the recent tube-amp conversion we looked at. But [Craig] did add some LEDs which illuminate the dial to help keep that stock look.

Upgrading a router with impeccable soldering skills

router

[Necromant] recently acquired a router that was nearly free. Looking his gift horse in the mouth, he hooked up a serial port to see if it could run some updated firmware such as OpenWRT. The initial findings were promising; it used the same CPU as the very popular WR703N, but this free router only had 2 MiB of Flash and 8 MiB of RAM – barely enough to do anything. His solution to this problem is in the true hacker tradition: just solder some more chips onto the router.

Upgrading the RAM was comparatively easy; [Necromant] found an old stick of RAM, desoldered one of the chips, and replaced the measly 8 MiB chip with a new 64 Megabyte chip.

The Flash, though, proved more difficult. Without the right code in the Flash for the radio test, the router wouldn’t be useful at all. The solution was to read the original 2 MiB chip, read the Flash from a  WR703, and combined the two with a simple dd command. This was written to a new SPI flash chip with a buspirate and a home etched board.

Oreo-creme hater builds Rube Goldberg CNC router to remove the Stuf

oreo-separator

Look, we understand the need to find a project to occupy your time and interest. So we’re not going to ask the wrong question (why?) for this one. This guy hates the creme that connects the chocolate cookies to make an Oreo. So he built a complicated system to separate the cookies and remove the creme. Check out the video after the break for a hardware overview (where we catch a glimpse of an Arduino RBBB) and a complete demonstration.

Although the project is a marketing gimmick for the company, we really love the fun they had making the video and the device actually works! Drop a cookie in the chute and it will be lifted into position for cleaving with a hatchet (we’re unsure what the string mechanism on the hatchet is for). The two pieces are then grabbed by some servo-powered grippers and transferred to a CNC router bed where a Dremel tool removes the residual creme before dumping the cookies out into your hand.

Once again, marketers should take note of this style of advertising. Notice the two main features achieved here: including a product in something we’re genuinely interested in and not being annoying (we’re looking at you Head-On).

[Read more...]

Dissecting a firmware image

dissecting-a-firmware-image

[Leland Flynn] did a great job of picking apart the firmware image for a Westell 9100EM FiOS router. Unfortunately he didn’t actually find the information he was looking for. But he’s not quite done poking around yet either. If you have never tried to make sense of an embedded Linux firmware image this serves as a great beginner’s example of how it’s done.

He was turned on to the project after port scanning his external IP and finding a random login prompt which he certainly didn’t set up. Some searching led him to believe this is some kind of back door for Verizon to push automatic firmware updates to his router. He figured why not see if he could yank the credentials and poke around inside of the machine?

He started by downloading the latest firmware upgrade. Running ‘hexdump’ and ‘strings’ gives him confirmation that the image is based on Linux. He’s then able to pick apart the package, getting at just the filesystem portion. His persistence takes him through extracting and decompressing three different filesystems. Even though he now has access to all of those files, broken symlinks meant a dead-end on his login search.