Category: Mobile Devices

DIY mobile services with Raspberry Pi

or "How to shrink a 30ft base-station into a three-inch Raspberry Pi"

 "Overcoming some seriously complex obstacles along the way, we successfully managed to route voice and SMS traffic through the computer – as well as implement the GSM mobile phone standard. If you are developing your entry into the competition and are looking for inspiration – or are just interested in what can be done with this exciting new technology – please watch our video."

"The Raspberry Pi was used to set up three pieces of software:

OpenBTS – this implements the GSM mobile phone standard

FreeSWITCH – this routes calls in a similar way to Skype

our own python features – a programming script that assigns telephone numbers to colleagues."

Web page link

Category: LLVM+Clang

LLVM + Clang 3.2 released!

It's a good day in the neighborhood both LLVM and Clang 3.2 have been released. You can read Chris's announcement  here- web page link 

There are many interesting goodies in this release so start your day by reading some Release Notes :-)

LLVM Release Notes and Clang Release Notes

Category: Tutorials

Write An LLVM Backend Tutorial For Cpu0

 "Preface

The LLVM Compiler Infrastructure provides a versatile structure for creating new backends. Creating a new backend should not be too difficult once you familiarize yourself with this structure. However, the available backend documentation is fairly high level and leaves out many details. This tutorial will provide step-by-step instructions to write a new backend for a new target architecture from scratch.

We will use the Cpu0 architecture as an example to build our new backend. Cpu0 is a simple RISC architecture that has been designed for educational purposes. More information about Cpu0, including its instruction set, is available here. The Cpu0 example code referenced in this book can be found here. As you progress from one chapter to the next, you will incrementally build the backend’s functionality"

Web page link

Category: C/C++

Pure virtual functions

 "Pure virtual functions provide a way to avoid defining base class member functions that have no meaningful implementation. "

"As in my prior articles, my sample classes represent an assortment of two-dimensional geometric shapes such as circle, rectangle, and triangle, all derived from a common base class called shape. The type hierarchy looks like: "

Blog page link

Category: C/C++

Object-oriented C is simple

Object-oriented C is simple: Blog page link

"Although most C programmers aren't proficient in C++, they can still use simple object-oriented practices. Here's part one in a series of blogs presenting simple ways to mimic object-oriented practices in C.

I'm a strong proponent of using C++ to write embedded systems firmware. The facilities C++ brings to bear enables developers to create highly-portable object-oriented code. One of the great benefits of C++ is that it enforces rules that require the writer to navigate in object-oriented channels of thought and action. Without the use of object-oriented (OO) practices, over time you will lose clear lines of independent behavior. The result will be hidden interdependencies of subsystems that should only be known to one another through defined public interfaces.

So what about C? You can use C in ways that mimic C++'s principles and to some degree enforce OO constructs. In C, you don't have the protection of the compiler. To use OO practices in C, therefore, you need to create a set of rules and play by them. Choose your rules carefully--the rules you follow can make your job harder or easier, especially when debugging. Unlike some rules that require a bit of detective work, a violation of the rules I present here will be as clear as day to spot even for the casual observer of the source."

Object-oriented C is simple: Part 2 - Blog page link

Category: Sensor Networks

Motion sensors de-mystified

"The motion-sensing sensors typically incorporated into consumer products include a 3-axis gyroscope, a 3-axis accelerometer, and a 3-axis geomagnetic sensor.  Each of these sensors exhibits inherent strengths and weaknesses with respect to motion-tracking and absolute orientation.  Recently, sensor “fusion” has found its way into consumer products as a method of overcoming the weaknesses of individual sensors.  Sensor fusion is a sophisticated type of software that combines inputs from various sensors to yield a more accurate motion sensing result, typically involving complex algorithms that can take into account well over several hundred variables if implemented properly."

Web page link

Category: Altera

Altera is shipping Cortex-A9 based Cyclone V SoC FPGA

"Altera Corporation (NASDAQ: ALTR) today announced the first shipments of its 28 nm SoC devices, which combine a dual-core ARM® Cortex™-A9 processor system with FPGA logic on a single device. "

 "The first devices Altera is shipping are low-power, low-cost Cyclone® V SoCs. " - press release web page link

Web page link

Category: Embedded Systems

Using virtualization to implement a scalable trusted execution environment in secure SoCs

"The digital revolution has been characterized by an explosion of new applications that take advantage of today’s high-speed broadband architecture. These include applications such as HD video streaming, gaming, VPN, social media, cloud computing and storage, and machine-to-machine (M2M) communications between embedded devices across both wired and wireless networks. Productivity and consumer entertainment has never been higher with these new applications, but this era has brought with it an increased risk of security compromises including piracy, IP theft and espionage, credit fraud and identity theft, and homeland security breaches, to name a few. Security has therefore come to the forefront of embedded system design. 

Static-based approaches for embedded system security which define secure and non-secure zones by partitioning separate hardware subsystems for each zone have been effective so far. However, more scalable and cost-effective approaches are required to address the needs of newer devices running multiple applications over several secure zones. This paper examines the use of virtualization for creating the requisite scalable trusted execution environment for secure embedded systems. It also provides an overview of MIPS’ existing and forthcoming solutions for virtualization-based security."

Web page link