Unsigned code running on Windows RT


A crack has been found in the armor of Windows RT. This subset of Windows 8 is designed to run on ARM processors. The payload listed in the image above allows you to run unsigned desktop applications on the OS.

We haven’t seen very much about the Windows RT package, so it’s nice to hear [Clrokr's] thoughts on it. As far as he can tell the system has not been watered down from its Intel-aimed (x86) counterpart. Rather, RT seems to be a direct port with what is called “Code Integrity” mechanisms switched on. There is a kernel-level setting, barricaded behind UEFI’s Secure Boot, which determines the minimum software signing level allowed to run on the device. This is set to zero on a Windows 8 machine, but defaults to 8 on an ARM device. [Clrokr] uses a debugger to insert the code seen above into a DLL file in order to reset that minimum signing value to 0.

Do you have a project in mind for which this is useful? We’d love to hear about it in the comments!

[via Reddit]

ARM powered rack mount USB test equipment


This is a device which [Limpkin] has been developing at his day job. It’s a high-speed testing interface for use with Physics experiments. We find it interesting because it uses an ARM microcontroller to implement CDC and MSD over USB.

The design is in two parts to make it work in a rack-mount situation. That big white connector allows cards to be swapped out. You can see the board on the right has a USB-A connector. When plugged in this enumerates as a control device (CDC) and a mass storage device (MSD) using fat32 as a file system.

The platform is being developed with open hardware and open source software in mind. If you’re working on a project that uses either of these USB functionalities this makes a swell reference. The ARM Cortex-M3 chip that he’s using is an AT91SAM3U but it should not be too hard to port the code for other similarly-capable ARM processors.

Building an ARM cross compiler on OSX


We’ve tried building our own ARM cross compiler on a Linux box and it’s no picnic. Luckily there is a free cross compiling toolchain available through Mentor Graphics (formerly called Code Sourcery G++). But those looking to develop on a Mac aren’t so lucky. There is help via a script, and [Michael] wrote a guide detailing how to use crosstool-ng to build an ARM toolchain on Mountain Lion.

Crosstool-ng is a script which automates much of what is needed when compiling all the different components. But there is a some groundwork that needs to be in place before you can run it. For instance, some of the tools that ship with OSX aren’t entirely compatible with the GNU tools the script is looking for. One example is ‘grep’. Mountain Lion has the BSD version of grep but it is missing a few of the GNU version’s commands used by crosstool-ng. [Michael] will guide you through this and a handful of other issues until you have a functioning toolchain up and running.

Hola! From a Spanish Speaking Drawing Arm

[Acorv] wrote in to tell us about his latest hack, a robotic arm that writes with a marker. In the video after the break, the arm is set to copy whatever someone writes in a touchpad. As you might guess from this video, the hack is written up in Spanish, but it’s nothing your favorite translator can’t handle if you don’t speak the language.

This robot it the result of improvements on his first drawing arm ‘bot featured here. The basic kinematics stayed the same in the arm’s second iteration, but the resolution was greatly improved by using belts to achieve a gear reduction. The second build also features mechanical reinforcement with an Erector-set style building set known as [Mekanex].

A simple hobby servo moves the marker up or down, and control is achieved through, you guessed it, an Arduino with a motor shield! Although from a different time, the way this arm is used is reminiscent of a mechanical writing automaton from long ago. [Read more...]

Netduino gets a huge upgrade

The Netduino, a dev board built around the .NET Micro framework with the goal of being compatible with Arduino shields just got a huge upgrade.

The new Netduino Plus 2 features an upgraded STM32 ARM Cortex-M4 uC running at 168 MHz, improving on the original Netduino’s ARM7 running at 47 MHz. In addition to some more processing power, the STM32-based microcontroller has twice the RAM and six times as much Flash memory. Also, Ethernet (10Mbps), a MicroSD card port, and of course compatibility with all Arduino shields – including the new Arduino ‘Revision C’ boards for the Leonardo – remains intact.

In keeping with the design goals of the Netduino, the new board uses the .NET Micro Framework running under Windows. It looks like OS X and Linux users won’t be left out in the cold for long, though; there’s a project to port the .NET Micro stuff over to Mono.

Tip ‘o the hat to [Jason] for sending this one in.

Developing with eBay-sourced ARM + LCD dev boards

eBay isn’t only about counterfeit designer handbags and boxes of all-marshmallow Lucky Charms, sometimes there’s actually something useful for sale. [Matt] found a bunch of Chinese-made ARM development boards with integrated LCD displays on the ‘bay, but without a reliable toolchain, these boards – as cool as they are – are nearly useless. Thankfully, he figured out how to do something with these boards, and neatly packaged everything into a VirtualBox image.

The boards in question usually include a 2.4″ or 3.2″ touch panel LCD, an STM32F103 ARM Cortex-M3 CPU, a microSD card connector, and sometimes a few other goodies like 16MB of Flash memory and an RS-232 port. An amazing amount of computational capability packaged into an easy-to-use form factor made even more awesome by their $40 price point.

Because these boards offer so much more than a common Arduino, a proper OS is in order. [Matt] looked over FreeRTOS and included a few demo programs for his Ubuntu-based VirtualBox image (available for download on [Matt]‘s site, it’s a dropbox, email us if you need some hosting, [Matt]) Never mind, see below.

Programming these boards can be done over a serial interface, but a JTAG programmer such as a Bus Blaster makes things very, very easy.

You can check out a few demos [Matt] put together after the break. It’s a very cool development that is much more suited for being integrated into an electronics project than a Raspberry Pi or other such high-power ARM board, and something we hope to see more of in the future.

EDIT: You know what’s really good for hosting Linux distros? Torrents. That’s [Matt]‘s distro and the HaD crew is seeding. Please seed.

[Read more...]

Turning a 600 mil chip to 300 mil

We’ve seen a few builds featuring NXP’s LPC1114 microcontroller before. This chip – the only breadboard friendly ARM microcontroller available – comes in a ‘still a little too large for prototyping’ 600 mil, 28 pin package. We won’t hazard a guess why NXP chose this rather large package, but the good news is it’s possible to shave this chip down to the more common 300 mil, 28-pin package used by AVRs and PICs.

In the video tutorial of this procedure, the chip is first taped down to a desktop CNC mill. 150 mil on each side of the die are removed, exposing the very cool-looking pattern of leads coming out of the chip. This isn’t enough area to solder, so the chip had to be further milled to expose some of the internal wiring.

After soldering everything to a set of pins, the new 300 mil package is covered in epoxy putty, milled down again into a nice cube shape and painted. Yes, the modified chip does work, and no, we can’t figure out why NXP chose a 600 mil package for this microcontroller over the far more common 300 mil chip.

Video after the break. Tip ‘o the hat to [Ian] for sending this one in.

[Read more...]