Jolla Sailfish OS & Simple weather app 
The new Jolla phone was released last year and has been out there for few months now. The phone runs Sailfish OS, which has roots in old Nokia / Intel MeeGo project.

When I got my device, there were no weather apps so I decided to write one. It utilizes the Openweathermap.org free API. Screenshots below:






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OSventures, part 2 
Since last blog post a lot has happened. First off, I was really busy for the few last months writing my master's thesis, so I haven't progressed on my OS or other projects at all. But finally, I got everything worked out and I graduated as M.Sc. in electrical engineering on 2013-12-04. After that, I have picked up the OS book again to continue the challenge.

So, last time I was trying to use GNU tools only for the projects in the book. After the break I felt that I was going nowhere with that and decided to go with the tools provided with the book for now. That way I could learn about programming OSses and could learn how to compile it on more general tools later (since compiling is the boring part anyways).

To use the precompiled tools, I only had to do some adjustments to the Makefile of the project, to use wine and replace some copy commands with GNU/Linux alternatives. Then I readily went onwards to do some graphics using the basic VGA, 8-bit 320x200 mode. (the book goes for the graphics first, since, well, it's fun to see the results on the screen and learn the smaller details on the way).

After setting up the palette, I made some simple line and square drawing. One of the interesting things there was how to draw lines, so I headed to wikipedia and found an usable algorithm, called the Bresenham's line algorithm, and it was easy to understand and implement in C by looking at the pseudocode.

Here's a screenshot of the program drawing the Finnish national flag, paying respect to the indepence day on 6th December:


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Starting to work on an Operating System 
While I was in Japan, I found this very nice book (in Japanese), which I didn't buy there since it was quite heavy..

After getting back to Finland, I tried to find such a book in English, but couldn't find one really, so I ordered the book from Japan.

It is written in very informal style, like teacher informally chatting with the student, which makes it very easy to read and easy to approach. All in all, I really like it!

However, the thing is it is mainly targeted for windows user, which is why it comes with a CD-ROM with customized compilers and assember for the project. Since I'm running Linux as my work OS, I wanted to do it with the tools existing for linux, that is GCC and GAS (GNU Assembler), dd and the like. I felt that, since these tools already exists, I should learn to use them rather than some customized tools that are harder to get. There is support page for the book, which has some tips for following the book on Linux. That is wonderful, though most of it is not quite what I want, for example they are compling the customized tools for linux or just usin WINE for the task.

So, hopefully I will be writing here about some endeavors I've faced. I have already started working on this.

See you next time!

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We should really have only one character encoding 
Really now, what's the point of having dozens of those encodings. I'm sure UTF-8 lacks somewhere, but I have managed with it so far.

Even this blog had some ISO charset as default for english. It could have been UTF-8 right away. Well, can't complain, since it's open source and I could easily modify it. But the software that are not open source.. They sometimes give me an headache.

So, I recommend everyone to read this: The Absolute Minimum Every Software Developer Absolutely, Positively Must Know About Unicode and Character Sets (No Excuses!)
I haven't yet read it all, but it makes sense to me so far.

Recently I also worked on an embedded project where I got into some problems with charsets.. Got it compiling nicely in Linux environment though. Sadly it's not working on the hardware yet. Maybe something more on that later.

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