This is FOSDEM 2018


Last weekend in ULB (University Libre of Bruxelles) took place the biggest Open Source event in Europe – FOSDEM.

With 678 talks, split in 55 devrooms this is something every open source enthusiast waits whole year.

It’s amazing how the organizers make such event possible, between 8 and 10 000 people all around the world come together at one place. If you want to meet some open source project, Linux kernel or Linux distribution maintainer there is great chance to meet him/her there.

FOSDEM usually is made in the weekend Saturday and Sunday, but traditionally starts with Friday evening welcome beer party at Delirium cafe. Do not be fooled by the name nobody go there to drink coffee.


Delirium usually can’t hold all people so the streets around it looks like this:


Every year this event become bigger and bigger. I was always wondering how they manage to keep their WiFi infrastructure in order with so many people attending. This year for the very first time the WiFi was impossible to connect to, so I guess we reach the infrastructure capacity 🙂

In Saturday the talks started, needless to say for me most interesting was the CAD and Open Hardware devroom.

One of the most anticipated talk there was about KiCad 5 new features.

Wayne Stambaugh the project manager started his talk with red T-shirt from Digikey and announced that Digikey made the single most significant donation to KiCad team just few days before the conference. So he said them “thank you” by presenting his talk wearing their red T-shirt.


It was very interesting to hear that Wayne got feedback from popular PCB prototype providers, that about half of PCB projects now they receive for prototyping production are made with KiCad! It’s amazing to see the progress KiCad made for the last 4 years!

I personally like more the T-shirt Wayne was wearing when he closed his talk 😉 KiCad team really like the complex boards we design with their product and this was very kind gesture.


Another interesting talk was Introduction to LibrePCB . This is the first time I hear about this project and it looks itneresting. The author is obviously capable young man and thinkered a lot about how to make component libraries more easy to use, but while I was watching the talk I was wondering (as many others) why the author just do not join KiCad, which is already well established project and leading as features and completeness. We all know that KiCad team is very small and more people joining the project will make much more sense than to re-inventing the hot water, because you do not like some feature in this popular project. Well this is the open source 🙂 and everyone is free to scratch his own itch, but I would love to see Urban Bruhin helping KiCad to become better instead to duplicate the work creating similar product alone.

Jesús Arroyo Torrens presented Icestudio – graphical way to program FPGAs. I would say this is quite entertaining and easy start for beginners with no previous knowledge about electronics.


Juan Gonzalez-Gomez (Obijuan) upgraded this talk with very entertaining presentation about what he did with Icestudio and small funny blocks he created. He is using his daughter as beta tester. I recommend you to watch this talk when the video is available.

Juan and Jesus are part of Spanish community working with FPGAs. You can see more about what they do on this site FPGAwars.

Staf Verhaegen shared his findings about is it possible today to implement ASIC design with open source tools. Very interesting topic, let’s hope the time Makers and small companies will be able to make their own chips with Open source tools is approaching.

My talk was about current TERES laptop status and the experience we got during the development with KiCad. Using FOSS tool like KiCad is great to make OSHW, but if you want to use latest features and the daily builds, they are available only via ppa repository for Ubuntu. This means if you use other distribution you have to build from sources every day. Windows daily builds are not available at all. This confuses many beginners who can’t manage to open our files when they want to study them as they use old builds (official Ubintu repository KiCad version is probably one year old, same for Windows version). My slides are now uploaded at Slideshare.

Other devroom talks I found interesting:

Exploiting modern microarchitectures Meltdown, Spectre, and other hardware attacks 

Programming UEFI for dummies 

Improving Linux Laptop Battery Life

Kodi and Embedded Linux

Linux as an SPI Slave

How to keep your embedded Linux up and running

Drive your NAND within Linux

Image capture on embedded linux systems 

New GPIO interface for linux user space 

It was nice to see three four other talks at FOSDEM by Bulgarian speakers!

Automating Your Lights with Open Source 
Turning On the Lights with Home Assistant and MQTT
Testing Red Hat Enterprise Linux the Microsoft way 

Current meta of video compression and probable futures

Overall FOSDEM is must see event for anyone who is interested in FOSS/OSHW.

Bruxelles is excellent location and offers lot to see, both Wizzair and Ryanair offer low cost flights to this destination and I don’t know where else you can drink beer from half meter glass (not half litter but half meter!) so looking forward to see you next year there!



FOSDEM 2018 the biggest European even for Open Source technologies is approaching!

Screenshot from 2018-01-23 11-08-37

If you have not been to FOSDEM yet you don’t know what are you missing 🙂

Thousands of people who support Open Source meet together for weekend in Universite Libre de Bruxelles, share ideas and talk on interesting topics for the community.

Here is the list of all dev rooms which will be available. Needless to say for us most interesting is the CAD and Open Hardware dev room.

Looking forward to see you there!

TERES I DIY Open Source Hardware Modular Hacker’s Laptop update


TERES-I DIY laptop first shipments started in September last year and we quickly sold the first initial production run. Immediately we start to get valuable feed back. Meantime the spare parts now are online and can be ordered.


Some of the feed back was quite pleasant like this one sent from Martin Krastev:


Този път ви пиша не с въпроси по подръжката, а като потребител на Терес с
няколкоседмичен опит и впечатления ; )

Знам, че по идея Терес-А64 е бил замислен като хакерски ноутбук, но вече
седмици го ползвам като машина за разработка:
1. Освен проектите, по които работя, Терес сам си компилира и
компилаторите, които ползвам — 2-та ГБ памет наистина правят паралелното
компилиране възможно, та дори да е само -j2 или 3 (нещата, които компилирам са сравнително тежки, и по-голяма паралелност вече опира до суоп файла).
Така че голямо благодаря за ъпгрейда на паметта!
2. Въпреки нищожното охлаждане на чипа, Терес успва да държи по-голяма част от времето 1152МХц, което беше много приятна изненада за мен.
3. Клавиатурата се оказа доста ергономична, въпреки че в началото имах
опасения, че ще е малка.
4. Избора на чип от програмна гледна точка също се оказа удачен – някои
прозиводители на А53-базирани чипове орязват архитектурни фийчъри (демек – инструкции), но allwinner не са от тях (за изненада! ; ) Това ми позволява да не се тервожа, че код писан за по-глеми армове може да не тръгне на Терес.
5. Батерията носи добре на натоварване – дълги компилации не угасват по
средата! : ) А и шината за sd карти държи прилична скорост – напъно
сравнима с вътрешния флаш (при прилична карта, разбира се), така че и
проблемът с допълнително дисково пространство за големи проекти е решен.

Ами това е засега! Исках само да ви кажа, че с Терес сте в правилната
посока, тъй както сте създали напълно ползваем работен ноутбук за арм
програмисти, което си е постижение!


Google translate does satisfactory translation so I would not challenge my English translation skills 🙂


There were two issues we couldn’t catch during our tests and went with the first lot to our very impatient customers:

1. LCD backlight, some LCDs cause the backlight circuit inductor L11 to resonance at annoying audible high pitch harmonic frequency caused by the 300Hz PWM.


According to best Murphy’s law practices this problem didn’t show at the first few laptops we build and tested, but when we shipped the first lot some people complained back about it, so we had to find quick solution.
1.1. adding bigger capacitor 100 uF in parallel to C204 was solving completely the issue, but the boards were already produced and shipped to customers;
1.2. adding double adhesive tape which to press the L11 to the plastic cover solved the issue in most of the cases, if this was not enough sealing the L11 with superglue also stopped the noise, which was caused by L11 vibrations, needless to say this was quick dirty and messy fix

Инфорамция как да ъпгрейднем фърмуер на touchpad и бутони:

This issue was completely fixed with adding 100uF to second production lot

2. Touch panel buttons issue. We run out of GPIOs on the keyboard board so ADC was used to scan these two buttons. Again everything was OK when we tested the few laptops we assembled in house, but soon after the shipment people start complaining that sometimes they press left button but laptop register right button and etc, quite annoying!
2.1. the problem was partially fixed with changing the firmware, we posted new keyboard PCB firmware and instructions on GitHub but this not always solved the problem
2.2. the good fix solution was to decrease the resistor values on the PCB and use 1% precision resistors instead of 5% used initially

We do apologize to all customers who had experienced such problem, we guess they are not many, but if someone has still such issue after the firmware upgrade we will send free PCB3 replacement, just please send us your requests to

In the current KITS this issue is solved.


The initial version of the Linux software was not in best shape, the community helped us a lot and we are now on the third release. Special thanks to Alexey Korepanov for reporting lot of issues and fixes! He also made his own Gentoo distribution for TERES-I at GitHub!


As you all know we suck at mechanical engineering and we had to find all plastic parts from Chinese laptop supplier. Some people asked about possible 3D designs of the laptop case but we are not capable to do this. So one of our customers Jeff Moe who obviously has mechanical engineering skills decided to re-design the plastics and make them as models in 3D printed format – he sends me pictures of his progress from time to time which I post here. So 3D makers be patient – there will be soon 3D printed designs and replacement parts for TERES!

EDIT: Jeff just noted me that the design is made by Brent MacKenzie from the Colorado Printing Project.



IMG_20180118_182208 (1)IMG_20180118_183356

It looks the LCD back plastic he designed is even easier to assembly than the original one.




I will post more in my next post about our progress in turning TERES-I DIY Laptop in portable lab with additonal FPGA board which makes from TERES component tester, Logic Analyzer and Digital Storage Oscilloscope with Sigrok.

TERES-I update. First feedback from our customers


Today we shipped all pending orders for TERES-I and we start to get valuable feedback from our customers!

First thing – we missed the magnet assembly in the instruction manual (blush). This leaded to laptops not go in suspend mode when lit is closed.

We updated this in the assembly manual 1.1 which is now on the web and included in the GitHub too in sources so people who notice typos and want to help improveing the Bulgarian-English language in which the manual is written.

Another issue reported immediately which we missed during our testing is that on small percentage of the laptops the LCD backlight step-up inductor cause annoying sound when LCD backlight is with 50% brightness.


It’s a interesting phenomenia as the backlight PWM is 300Hz which is not possible to hear, but when LCD backlight is switch ON and OFF high current surges are happening and some harmonics cause mechanical resonance with this inductor.

The solutions may be few:

  • play with PWM frequency to get away from this frequency which cause the mechanical resonance – pure software approach which need lot of experimenting
  • adding small double adhesive matt on top of the inductor which make contact with the back plastic and this way absorb all vibrations – we start to add this mat as soon as we discover this issue to all laptops no matter if they buzz or not. Not very aestetish but quick and dirty solution:


  • Add more capacitors to the PWM power supply which to handle this current surge, adding 100 uF seems to remove the problem, but the first lot was already assembled and many laptops are already shipped – so this we will implement in the second assembly.


We have two reports about problems caused by the touch pad after “apt-get update / upgrade” we have to look more closely into this issue. For the moment we do not recommend you to update and upgrade your Ubuntu packages or if you do this and something stop working to revert to the original image – this is pretty easy just download the image write it to SD card, boot and run the eMMC copy script.

TERES-I Do It Yourself Open Source Laptop update


We are glad to tell you that we finally have TERES-I released!

It was long way but finally we have laptop which works satisfactory to be released.

What we changed since revision B?


Main board now is with 2GB DDR3 ram and 16GB eMMC Flash memory. We add two new connectors CON3 and CON4 to interface the further FPGA module which will turn TERES-I in oscilloscope and Logic Analyzer.

The debug UART multiplexes now with Headphones, so you can plug serial cable to headphone jack and re-direct Debug console UART to Headphone jack. After you finish debugging you can restore Headphones functionality to this jack. We work on USB-Serial cable with headphone jack for the laptop.

We got new 9500mAh battery which now is in TERES kit.

Another improvement is 5V 3A adapter which allow battery to be charged to full in 3 hours. The adapter has charge indicator and comes with convenient 3 meter cable, so you can lay on your bed while your laptop is connected to power supply.

Please give us some days to update all latest Hardware files on Github.

Work-in-progress User manual and Assembly instructions are here.

The software is let’s say about 90% ready state, but works satisfactory even now.

The laptop comes with pre-installed Ubuntu 16.04 LTS with Mate, Firefox browser, Video player, Open Office, Arduino IDE and IceStorm for FPGA development. We will try to include KiCAD later.

Python libraries to access I2C, SPI, UART, GPIOs will be add when ready.

FPGA module with ADC/DACs/IOs will be ready in the next months, it will be easy to insert inside with the other existing boards.

TERES-I is now for sale.

This project took lot of time and we have long list of registered interest for ordering, bigger than the number of laptops we could build in the first run. We guess many of these registered users are duplicated for black and white version and will take just one, but be prepared that after you order your laptop will not be shipped immediately but in 2-3 weeks (or less) depend on workload and number of orders to be processed. Once/if the first run is sold we will make the laptop out of stock and will work on second run which may take few months to complete, but we will produce this laptop until there is interest for it, so if you do not succeed to order during the first run, do not give up 🙂


EDIT: very important notice to add: TERES-I is not designed to scratch everyone’s itch. If you want high performance laptop. If your work involve 8-16-24 core processor power and 4-8-16-32GB RAM memory to do video editing or to compile Linux kernels and Android distributions etc. this is not your laptop! TERES-I software is far for complete and not using 100% performance and features of A64 chip yet, it will work much better and faster in future, now it’s work satisfactory for daily work in motion.

When TERES-I was designed we wanted to make laptop which allow you to travel and do internet browsing, emails check, embedded code development, programming arduino, making PCBs etc. With the further modules it will become more like traveling laboratory to sniff protocols on hardware level, to generate signal patterns etc.


TuxCon-Kitty the OSHW TuxCon 2017 conference badge soldering kit is in the web shop


TuxCon 2017 conference was 3-4 of June in Plovdiv. Specially for the conference we made soldering kit badge, designed with KiCad and programmable with Arduino IDE.


Here is how it looks assembled:



The project is hosted at GitHub. It’s good way to learn how to assembly SMT components and how to install, setup and program with Arduino IDE.

Do not hesitate to make pull request for your Arduino sketch if you manage to compose your own music with this board 🙂


What happens with Arduino project?



Arduino is always pointed as example for successful Open Source Software and Hardware project.

With thousands of contributors and millions of users this project is bespoken leader among microcontroller development.

No one remembers the tools used before Arduino.

There were few attempts to fork it for other platforms like Maple for STM32, Energia for MSP430, MPIDE for PIC32 but they never managed to make enough critical mass outside the main Arduino project and then simply were absorbed in Ardino IDE when it got possibility to merge different processor platforms. That was the end of all forks.

All this amazing progress would not be possible without Arduino being Open Source and the help of the thousands contributors.

With the success came the money and as always they were subject to disputes and all we know for the battles inside the Arduino team in the court.

Last year the problems have seemed to be resolved and Arduino Foundation was created and this was announcement as “new beginning”, but meantime some bothersome things were noticed by Open Source community.

All hardware projects listed on are announced to be open source hardware, but none of them comply with OSHW definition. The sources are with status “coming soon” years after their release, or where these sources are available there are hidden black boxes which actually spoil the whole idea to allow other people to study, modify, improve and reproduce the design.

Makezine has published article this month with some bothersome facts about Federico Musto who seems to own major shares in the new formed Arduino foundation.

Wired also published article on this issue

Meantime Philip Torone from Adafruit posted message on OSHW mailing list with list of boards on with problems in OSHW compliance

So many people now ask themselves the question: Is Arduino project hijacked and turn in to Closed Source Project and how this will affect the Arduino community in future?

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