Jansman.eu / Ealanrian.nl

Cmake for Arduino and Clion

Sat, 14 Feb 2015 16:30:00 +0000

Cmake for Arduino and Clion

For a project I just started working on I wanted to use Clion with Arduino, since there is no Arduino plugin or support for Clion yet I had to figure out a way to do this with Cmake. In this post I'll try to explain what to do.

Required resources

Ofcourse the Arduino SDK needs to be installed and a Cmake library is required. For this I found Arduino Cmake which can be found at https://github.com/queezythegreat/arduino-cmake.

The project

So lets get started. First create a project directory, mkdir ~/workspace/ArduinoCmake and move into the directory. cd ~/workspace/ArduinoCmake. Let's get the toolchain by going a git clone git@github.com:queezythegreat/arduino-cmake.git This will get the CmakeFiles needed to do arduino related tasks like uploading it to the Arduino. Next we create a source file: nano main.cpp in this file we put a simple demo:

#include <HardwareSerial.h>

#include <Arduino.h>

int incomingByte = 0;    // for incoming serial data

void setup() {

    Serial.begin(9600);    // opens serial port, sets data rate to 9600 bps

}

void loop() {
    // send data only when you receive data:

    if (Serial.available() > 0) {

        // read the incoming byte:

        incomingByte = Serial.read();

        // say what you got:

        Serial.print((char)incomingByte);

        }

}

This demo will do a serial echo so we can send data to the Arduino which it will echo back. Next we create the CmakeLists.txt: nano CMakeLists.txt and in this file put the following: cmake_minimum_required(VERSION 2.8.4)

set(CMAKE_TOOLCHAIN_FILE arduino-cmake/cmake/ArduinoToolchain.cmake)

project(projectName)

set(ARDUINO_DEFAULT_BOARD mega)

set(ARDUINO_DEFAULT_PORT /dev/ttyUSB0)

link_directories(arduino-libraries)

generate_arduino_firmware(projectName

    SRCS main.cpp

)

I will highlight the important lines: The set(CMAKE_TOOLCHAIN_FILE line tells Cmake where the Arduino toolchain is located. This line must be before the project line. The next lines, ARDUINO_DEFAULTs, tell the Arduino toolchain which board is used and on which port it is located. In the generate_arduino_firmware command we tell the toolchain which sourcfiles to use.

Building the project

To build the project create a build directory: mkdir build and move into it: cd build. Next use cmake to build the project: cmake ../ and this creates make file. To build the project use make and to upload the project use make upload

Honours Weekend

Sat, 14 Feb 2015 00:00:00 +0000

The Honours weekend

This weekend the IT students and alumni participated in a hackaton like weekend. A weekend filled with fun, drinks, programming, presentations and more. In this post, which will be updated during the weekend I'll try to capture the vibe we have here on the island called Terschelling.

This post is work in progress and will be updated multiple times this weekend.

The Location

One of our sponsors offered us the location namely Hotel De Walvisvaarder on Terschelling. They kindly offered us the rooms and meals to use. This beautiful location on the Island of Terschelling. This is one of the island in the Netherlands.

The program

To have some guideline on what would happen during the weekend the guys organizing it created a program. The program started on Friday the 13th at 09:55 with the departure of the boat and during the rest of the day presentations were planned as well as the pitching of some idea's. Friday night after diner teams formed and the hacking started, more on that later.

On Saturday one more presentation interrupted the work-flow, even though this presentation was on the subject of work-flows namely agile working. The rest of the day was filled with programming, hacking, games and other stuf which happens when you put 16 programmers in one room.

The Projects

This is the first post using Jekyll and github pages.

Sun, 25 Jan 2015 00:00:00 +0000

This is the first post using Jekyll and github pages.

As of now the site has been migrated to github pages. The main language will be English, though some posts might be written in Dutch due to the subject or if they are older

Migration and updates

In the coming days and weeks the old posts will repear here and the site will be updated.

Google summer of code [Dutch]

Sun, 27 Oct 2013 19:21:00 +0000

Google summer of code, wat is het

Google Summer of Code (GSOC) is een project van Google om studenten te betrekken bij opensource projecten. Door studenten te betalen om aan uitdagende projecten te werken met mentoren uit de projecten word er geprobeerd om de studenten in de community's te krijgen.

Hoe werkt het?

Tijdens GSOC werk je voor een periode aan een project, in mijn geval Apache Celix event admin, en word je begeleid door een mentor vanuit de organisatie. Om te mogen deelnemen aan GSOC moet je je inschrijven, deze inschrijving bestaat uit een project idee en een motivatie waarom je mee wilt doen. Er zijn verschillende organisaties die van te voren al vast staande projecten aanleveren waarop je dus kan solliciteren of er is een idee waarop je een plan schrijft hoe je het wilt uitvoeren.

Je inschrijving word beoordeeld door de organisatie waar je voor gaat werken en ze zullen eventueel nog vragen stellen om opheldering te krijgen. Als alles goed gaat word je geaccepteerd en mag je dus mee doen aan GSOC.

Tijd

Officieel duurt GSOC 3 maand, van mei tot augustus, heel toevallig lopen die gelijk met de Amerikaanse zomervakantie. In die 3 maand is het de bedoeling dat je programmeert en actief deel bent van de community. Ik kom verder op nog terug op hoe ik de tijd heb ingedeeld.

Controle

Google heeft tijdens GSOC twee controle momenten, ongeveer halverwege en aan het eind. De halfweg controle bestaat uit een enquête die jij en je mentor invullen en wanneer dit positief is mag je door met het project. De eind controle bestaat weer uit een vragen lijst en er word verwacht dat je code samples upload. Dit is om te controleren of je ook daadwerkelijk hebt geprogrammeerd.

De beloning

Google betaald dus studenten voor het werk wat er aan de projecten word gedaan. In totaal was het dit jaar $5000 voor de student en $500 voor de mentor. Dat was dit jaar een totaal bedrag van ongeveer $5000000 wat betaald werd. Hierbij komen dan nog de goodies en de overhead kosten voor controle en dergelijke bij. Google gooit dus redelijk met geld.

Het geld

Als je geaccepteerd word voor GSOC krijg je al direct een deel van het geld. Je krijgt namelijk een prepaid credit card toegestuurd, met het Google logo er op, waarop $500 staat. Je hebt dus nog niks gedaan en al $500 dollar in de pocket. Als je de halfweg evaluatie door komt krijg je de tweede betaling, $2250 word op de creditcard bij geschreven. En als laatste krijg je bij het succesvol afronden van de eind evaluatie nogmaals $2250 dollar.

De echte beloning

Die $5000 is natuurlijk allemaal leuk en aardig maar daar doe je het niet voor. Het zijn de goodies waar je voor werkt. Samen met de creditcard krijg je aan het begin een Pen, een notebook en een sticker met de logo's van het jaar er op. Als je de eind evaluatie haalt krijg je echter het meest belangrijke object, het T-Shirt, Oja je krijgt ook nog een certificaat van deelname leuk voor naast al je andere certificaten .

Apache Celix en de event admin

Ik heb zelf mee gedaan aan GSOC op een project waar ik tijdens mijn stage mee te maken heb gekregen, Apache Celix. Apache Celix is een project wat als doel heeft een OSGi implementatie te maken in C. Tijdens mijn stage heb ik aan de Remote Service Admin gewerkt en mijn stage begeleider leek het wel leuk om als GSOC project de event admin te bouwen.

De aanmelding

Voor mij was de aanmelding relatief simpel, ik heb namelijk zelf mee geschreven aan de opdracht omschrijving en ik werd beoordeeld door mijn stage begeleider. Ik was dus ook vrij snel klaar met de aanmelding en ik heb ook maar 1 aanmelding geschreven. Ik kan helaas mijn aanmelding niet meer bekijken dus deze komt niet in het topic terug.

De tijdsindeling

Zoals al gezegd is het project afgestemd op de Amerikaanse zomer vakantie. Dit was best lastig aangezien ik nog moest stage lopen tot 1 juli. Omdat ik dus geen tijd zou hebben om al in mei te beginnen heb ik in mijn aanmelding vermeld dat ik van 1 juli tot en met 31 augustus zou gaan programmeren en daar tussen 1 week vakantie zou hebben. In totaal heb ik dus maar 8 weken gewerkt aan GSOC. Dit was echter geen probleem en zelfs redelijk normaal aangezien er ook mensen zijn die wel mee doen maar geen vakantie hebben, de mensen op het zuidelijk halfrond.

Het project

Dus 8 weken werken aan een project in C waar je nog niet heel veel ervaring in hebt. Leuke uitdaging. Ik heb de eerste 3 weken verpruts, er is echt niks fatsoenlijks uit gekomen in die weken en ik heb ook alles weg gegooid. Mijn mentor was namelijk een klein detail vergeten te melden. Hoe de spec, geschreven voor Java, geport kon worden naar C. Nadat dit eenmaal duidelijk was ging het als een speer en het resultaat is te vinden op bitbucket [1].

Wat heeft Google er aan

Google smijt tijdens GSOC behoorlijk met geld. Er word $500 dollar aan elke student gegeven voor er ook maar een letter code staat. Hier moet dus iets achter zitten en dat klopt. Google gebruikt GSOC om potentiele recruits te vinden. Ook maakt Google gebruik van de projecten of een deel van de projecten die meedoen aan GSOC.

Volgend jaar

Volgend jaar is de tiende editie van GSOC. Er zullen wat dingen veranderen, de beloning word met $500 verhoogd, er worden meer studenten toegelaten en meer projecten toegelaten. Of ik zelf mee ga doen weet ik nog niet zeker. Misschien nogmaals als student maar misschien ook wel als mentor, er van uit gaand dat ik voor die tijd commitor kan worden bij Celix.

Dit topic

Het lijkt me leuk om dit topic te gebruiken om ervaringen uit te wisselen, projecten op te zetten en om te praten over GSOC. Ook discussiëren over het ethische van een dergelijk programma is interessant.

[1]: https://bitbucket.org/Ealanrian/gsoc-celix-eventadmin

High performance message queues in clustered environments

Sun, 28 Apr 2013 19:31:00 +0000

To complete my bachelor course in Computer science, I have to complete an internship. Since I wanted a challenging project and a project in an inspiring environment I ended up at a High tech company, which was surprisingly close to my home. Sadly the public transport system isn't very good in this part of the Netherlands so I bought my first car, but that's for another post. The internship assignment consisted of research into message systems and a part implementation. So far I have completed most of the research into message systems. In this post I'll talk about the message queue systems researched in this project and the different ways of working with messages they have.

First

Kraków 2012 - DIMA

Sat, 14 Apr 2012 16:43:00 +0000

So it's time to talk about my trip to Kraków. For those who don't want to read the whole story: it was awesome.

Sending signed e-mails using php

Sun, 11 Mar 2012 14:47:00 +0000

Last term we had to build a "secure" website. This included using SSL/https and signed e-mails. Since we were going to build a website and I'm an experienced PHP web developer we decided to go to work with PHP. This gave us a small problem, how do we sign e-mail messages using PHP. Using multiple how-to’s and tutorials I was able to figure it out. Helping others being able to find it quicker I’m writing yet another tutorial hoping to help people to get it working in an hour instead of a few days. In this tutorial I’m not going into details about creating certificates and keys to use, I’ll only talk about how to sign emails using PHP. I will include some quirks you could encounter when using Xampp or some other form of apache on windows.

There are a few things important to know when signing emails and doing this on windows. Windows does not like relative paths, use absolute paths. The headers and the content of the email send should not be changed after signing. If you do the verification, the thing it’s all about, will fail. You should know a thing or two about PHP before using this tutorial, it’s not hard but if you don’t know PHP it is. Having said that lets get to work.

The first part is creating files to read from and write to, why need them will become clear later. In the folder you are working create two files, msg.txt and signed.txt and make sure they are writeable by PHP, in Windows create them as the same user running apache, on Linux chown them to apache or chmod them to 777. After that create a file called mail.php or something. This file will contain the class.

In the file you should create a class and a method, I have called them mail and sendSignedMail. The method has $toAdr, $subject, $message as parameters, these will be used later. First create a few variables in the method.

$prfile, this will be the private key pointer. I have placed it in the same folder as the file so the path is $prfile = 'file://'.realpath(dirname(FILE)).'/key.pem';
$pufile, this will be the public key pointer, $pufile = file://'.realpath(dirname(FILE)).'/cert.pem';
$msg, this is a pointer to the previous create msg.txt, $msg = realpath(dirname(FILE))."/msg.txt";
$sign, this is a pointer to sign.txt, $sign = realpath(dirname(FILE))."/signed.txt";

Having those variables is just to prevent typing those paths all the time. Now let’s start with some code.

$fp = fopen($msg,'w');

fwrite($fp,'Content-Type: text/html;charset="us-ascii"Content-Transfer-Encoding: 7bit

'.$message);

fclose($fp);

Do not copy this code but type it since it won’t work because of whitespace problems. First I open the msg.txt and create a filepointer. After that I write the message and a content header. This header is to tell mail clients how to read this message. After that I close the file again since it is not needed to keep open.

openssl_pkcs7_sign($msg, $sign,$pufile, array($prfile,'onzebank'),array("To"=>$toAdr,'subject'=>$subject));

Using openssl_pkcs7_sign will sign the message. What it does is take the content from the msg.txt file create a hash from it using the private key, the public key and also including the subject and the destination address.

Now you have a signed message, but it is on your server and not in the destination email box. Let’s make that last part work. I could open signed.txt get the content and mail that to the destination. That will get the message to the destination but not usable. Since the signature won’t be correct. To do it correctly we first have to get the content from signed.txt with:

$data = file_get_contents($sign);

Now we have all the data we now have to separate the message form the headers which are also in the data variable. This is also the part where a lot can go wrong because of white spacing.

$parts = explode(‘

’,$data);

This will explode the data on triple new line sequence, if you get verification errors this is the part to look for trouble.

Now we have the headers and the message, $parts[0] and $parts[1] respectively, now we can send the email.

Mail($toAdr,’’,$parts[1],$parts[0]);

I am not setting the subject using the mail function since that would mess up the headers and thus the signature. After this I clean up the files to prevent data to be stored or lost or messing around with the next mail.

$fp = fopen($msg,'w');
fwrite($fp,' ');
fclose($fp);
$fp = fopen($sign,'w');
fwrite($fp,'');|
fclose($fp);

Just to be nice I also added the file containing the class: mail.php

The cave project

Mon, 13 Feb 2012 19:46:00 +0000

So I have been talking about the Cave project a while ago. And I promised to give more information about it, in this post I will tell a little bit more about the project and the outcome.

Let me start with saying that we didn't get to the point where we wanted to be. In the beginning of the project the plans where big and expectations high. The project was about creating a room for dementing elders to relive and re-experience past events and memories to help them become calmer and hopefully help to slow down the loss of intelectual capacity. The Cave, computer aided virtual enviroment, was supposed to work with video, audio, light, sent and more to help them relive those events.

Since I already told you that we didn't get to that point what did we do? Well we created a base for the next project group to work with. We searched for the hardware and software and figured out how to make it work. We have written plans and recommendations and build a skelleton for the next group to work with. We all feel sad because we didn't get to work with all the hardware and cool stuff, but this is how it works in real life and I'm proud of what we did.

So why did we not get to the point where we wanted to be? Well first of all communication was a problem. None of us had ever worked for a real contracter before and we didn't know how to get information when we needed that. We have been waiting for nearly 5 weeks before we figured out that we should just go instead of wait for info and do nothing. This gave us the freedom to do what we do best, improvise. This resulted in us creating something which is to form a base for the Cave project. We sure hope it's going to get somewhere soon.

Hanze mail in Windows Live mail 2011

Fri, 13 Jan 2012 18:59:00 +0000

After posting the how to for getting hanze mail in a mail client I recieved a lot of comments on how to do this in windows live mail. So here is the how to to get Hanze mail in windows live mail 2011.

go to the accounts window, options button left side top of the window-> options-> email accounts
press the add button
Select E-mail account.
fill in your hanze mail adres, i.e. somename.somelastname@st.hanze.nl, your password, your real name and select the manual server configuration box.
now you will see the serverconfiguration screen. This screen looks complicated but I'll try to talk you through it.
1. set the servertype select box to IMAP
2. bellow the servertype selectbox fill in webmail.hanze.nl as server adress
3. set port number to 993
4. Select the secure connection(SSL) select box
5. Select password verification in the verification select box
6. fill in your username which is not the same as your email adress. For students this is the student number and for teachers the 4 letter code.
7. on the righthand side of the screen is the part for outgoing mail. Set this to the out going mail server of your internet provider for example ziggo uses smtp.ziggo.nl on port 2
press next and there you have it.

Folding bike

Mon, 09 Jan 2012 19:43:00 +0000

As some people might know I ride a folding bike. This is because it's free to take with you in the train and it's a lot quicker as riding the bus from the station to college. My first folding bike was/is a Ventos folding bike as shown below. It's a prety good bike but after me abusing it for nearly 2 years now it starts to twist and bend. Already had a broken securing pin and the chain tends to run of a lot.

The replacement:

It's a Beixo compact a folding bike without a chain. It uses a cardan shaft to transfer the energy from the pedals to the wheel. This should be a maintanance free system and also it is no longer possible to have a lose chain. I'll probably get the Beixo this week and hope to review it next week.