Few years back I started thinking about how much information could be extracted from a phone’s inertial sensors to guess some sensitive information such as PIN / UnLock Codes / other passwords. …

Pebble ( http://www.getpebble.com) is a smart-watch pretty popular for rasing more than $10 million from a Kickstarter campaign. Features a STM32 microprocessor as can be seen in wikipedia ( http://en.wikipedia.org/wiki/Pebble_(watch)). Pebble’s update package contains a bootloader image but I wanted to dump what really is on the internal flash. In…

Almost every company manufacturing Embedded Systems produce their own boards with their very own peripherals, which of course, need to be initialized when the boards is powered up. They can go from simple leds, to amplifiers or external appliances, but what they usually share is that they depend on GPIOs…

A few days ago I hit an awful bug in the iOS’s TCPI/IP stack which drove me crazy for a while since everything worked fine on other devices except a brand new iPad. The problem appears when UDP packet’s payload is larger than 9200 bytes; Beyond this limit the app…

If some day you find yourself debugging u-boot, or maybe another bootloader, you will probably face a problem when setting breakpoints at some symbols; the application doesn’t stop where you have told the gdb to. Bootloaders usually are written to the system’s flash so the microprocessor starts executing there at…

After my last post I got a request from @trufae asking for a benchmark against Android’s bionic library so there I go. I begun compiling the available bionic’s strlen version and running the same test as in my previous post. The first thing I noticed reading the bionic’s strlen version…

Note: This optimization are for an ARMv5 processor (arm926ejs) further improvement could be achieved in a newer ARM versions The next function I want to play with is strchr() used for locating a char in a given string; returns a pointer to the first occurrence of the character or NULL…

Few weeks ago I started a personal project to enable lua programming under u-boot to allow easy access of peripherals and create small embeddable initialization scripts which I have missed during professional Embedded Development. Another goal of this projects is to optimize u-boot’s ARM code so the first optimization go…

The paper presents a series of techniques which goal is to detect the presence of RF signal from different devices such as bluetooth, Zigbee, etc. They main contributions is the use of commodity WiFi adapters which allows anyone to use the solution proposed. The image below show an schematic view…