Thoughts dereferenced from the scratchpad noise.

Latest posts


Linux (Debian Wheezy) on Lenovo y510p

Published at May 16, 2014 · Piotr Król ·  4 min read

After long analysis I decide to buy new laptop. I had about $1000 (or 3000PLN) and most important things to me were: i7 CPU - because of performance (of course at least 4700 series) SSD - again performance 17.3” - working space no OS/FreeDos/Linux - I will not pay additional fee to M$ for system that I won’t use Full HD resolution at least 8GB RAM non-glare display First I realize that my budget is to small for such a hardware....

Categories: os-dev

Improve productivity with Google history using bookmarks and Chrome extensions

Published at July 30, 2013 · Piotr Król ·  5 min read

The idea of this post is very simple (as usually) and I wonder why I didn’t thought about it earlier. The point is to use history of your Google queries to improve productivity. Most of things that we google can be replaced for example by browser extensions, bookmarks or rss feeds. That’s how we can gain few additional free seconds on each google-type-click cycle. Statistics Depending on different factors we spend a lot of time in browser....

Categories: miscellaneous

0x6: Root file system for embedded system

Published at June 7, 2013 · Piotr Król ·  10 min read

Introduction To make our embedded linux work as virtual development platform we need some environment after booting. There is many approaches to get working root file system but I will use the easiest one as an exercise. I don’t want to create full embedded distribution (this is good plan for future works). Right now I will be happy with simple initramfs based on BusyBox. For all interested in creating own root filesystem there are few places where you can find information:...

Categories: os-dev

0x5: Qemu network configuration and tftp for Virtual Development Board

Published at June 7, 2013 · Piotr Król ·  7 min read

Introduction This was not trivial task to me. As usual google is your friend and RTFM works. First we will set tftp which we use to download modified kernel for U-Boot. Second I will show how to setup bridged network for QEMU needs and finally we will perform some basic test of our setup. Let’s go. Setup tftpd First install: 1 sudo apt-get install tftpd tftp Make sure that /srv/tftp is writable for your user....

Categories: app-dev os-dev

0x4: Linux kernel for embedded system

Published at June 7, 2013 · Piotr Król ·  3 min read

A little history Thinking about embedded linux probably leads to first try of porting linux to different architecture. I did google research (I know I should probably read mailing list archive) and found that there were few attempt to port linux to different platform. There is no clear information about which port of linux was first. This is probably because many hackers didn’t report their effort. Arguably earliest out-of-tree version was probably for Acron A5000 (arm), Motorola 68000 (m68k) around Spring/Summer of 1994....

Categories: os-dev

0x3: Embedded board bootloader

Published at June 7, 2013 · Piotr Król ·  3 min read

What is bootloader ? It is a program written to bring up more complex code (eg. kernel). On very simple system it can even not exist. Bootloader should prepare all required hardware that kernel or different operating software will need at its start point. It is hard to create cross platform bootloader because of variety of system requirements. Why we need bootloader ? The true is that we don’t :) because we can simply pass kernel and initramfs as parameters to QEMU, but it is not common practice for real development environment....

Categories: firmware

0x2: Toolchain for Virtual Development Board

Published at June 7, 2013 · Piotr Król ·  4 min read

Introduction This is probably the most complicated topic of all related to embedded development but we need to deal with it at the beginning. I read a lot about toolchains but still don’t know enough to explain details. I think that best answers are in crosstool-ng documentation. What is toolchain ? Toolchain as the name said is a set of tools chained together, so output of one tool is the input for different tool....

Categories: app-dev os-dev

0x1: Qemu as an environment for embedded board emulation

Published at June 7, 2013 · Piotr Król ·  2 min read

Table of contents Introduction Compilation Kudos Introduction QEMU is a CPU emulator using dynamic binary translation to convert guest CPU instructions into host CPU instructions[1]. It supports many architectures from x86, through ARM and MIPS, to MicroBlaze. According to compilation configuration target list QEMU targets 26 different softmmu types. Only for ARM it supports 33 machines (like ARM Versatile/PB (ARM926EJ-S) or Samsung NURI board (Exynos4210)) and 28 CPUs (with cortex-a9 and pxa270)....

Categories: app-dev os-dev

0x0: Intro to Virtual Development Board building

Published at June 7, 2013 · Piotr Król ·  2 min read

Preface There are many reasons why ambitious programmers should care about huge rush in embedded market. IMO there is great potential in it. I don’t want to go deep into this but take a look at all tablets, phones, smart TVs and other cool stuff like wireless in you washing machine or refrigerator (ok this two are right now only a gadgets :) ). This is all embedded. Another thing is that wages of experienced embedded developers are really high....

Categories: firmware

Workflow improvement with Open Source tools - part 1

Published at May 16, 2013 · Piotr Król ·  5 min read

Introduction I want to start a series of articles to describe how I improve my workflow with geeky Open Source applications. I will concentrate on terminal applications that I try to use in my GTD process. Terminal Solarized gnome-terminal If you already don’t know what solarized color scheme is then please take a look at this page. To install solarized colorscheme in gnome-terminal simply follow instruction from this git repository....

Categories: miscellaneous