The Py Hole

Making C my b*tch!

2011-08-04T14:45:00.000-07:00

Well as of yesterday I have decided it was time to learn C. A language which I had briefly fought with whilst learning to program my arduino but never quite come to grips with.

With third year round the corner and the course largely based on knowing C and it's legendary pointers I thought it best to start from scratch before it's too late.

The first challenge would be how do I create, write and compile these C programs??.........Well as I found out there's no textbook answer to that one, more of a if it feels right then go with it methodology.
So after having spotted a friend using Sublime text I downloaded it and found out my fresh install of Ubuntu 11.something had a C compiler already installed (gcc) I was away, well sorta.

Next on my list was to find a copy of the recommended reading my university suggests which is none other than "The C Programming Language" by B.Kernighan and D.Ritchie. Which unsurprisingly there was a pdf of online which a college/university was hosting weirdly enough.
Whilst I was searching I also came across some documentation from Stanford University called "Essential C" as well as others, which funnily enough I've used more than the former book. I also managed to find some other extended documentation by Stanford which has been very useful.

Anyhoo, after reading up on "Essential C" I set about trying to push aside my now object orientated mind and dust off the procedural chest in my mind. For a moment I panicked thinking "How do I create a function to edit a variable created in another function?!AHH". That moment quickly passed as pointers were first introduced and I was sat there blankly staring at oodles of * and & wondering "Eh?".

So to start I wrote the un-original "Hello world" message to then move on to accepting char input.
Then just to spice things up a wee bit I thought I would try writing a linked list data structure in C. Hoping this help me get to grips with pointers, as a linked list is at it's core pointers.
Soooooooo, on I went, learned about structs, typedefs, how to actually use a pointer and dereference it, whilst managing to do the rookie mistake and totally forget about local scope with creation of variables. In python for example if you returned a variable created in function it would return the value nicely, with C however it's a no no, it doesn't say a word so all seems well but when you run the function, pass back the variable, the variable gets destroyed upon exiting the function and all that's left is some random useless data.
Which is where pointers came in and saved the day :|

To cut an already long story slightly shorter I learned more about pointers and how to access them etc.
To which I then learned I needed to learn about the C heap and how to use it as a dynamic data store with malloc().

Soooooooo after two days of learning and tinkering I've created a working (awesomely) basic linked list generator and now one step closer to my far away goal of "Making C my b*tch!".

:)

Back again. This time for real!

2011-07-30T16:48:00.000-07:00

Well it's been almost a year since I last posted something......lets get to it.

This summer I've been keeping myself busy juggling small projects and trying to learn some japanese.
I've picked up a couple of Thin clients(10zig RBT402) off of ebay for some always-on computing power(torrent downloaders,music server,shairport server).

I've also been trying to clean up and upgrade my media server I built at the end of last summer. I've built a hard drive rack and attempting to speed it up/tidy up the raid array.

Last week Ebuyer on ebay reduced the Hannspree Hannspad from £250 to £150, which has some decent specs(Tegra 2) for a tablet at that price, sooooooo I thought about it.......found out I had an ebay voucher which knocked off £25 quid just as there were four left, at which point my crazy gadget side took over and pressed buy it now in a flash!

As I waited I looked up straight away for any roms available and found out it was a relatively untouched device, but since the sale it very quickly built up a community and by the time my hannspad came a super fast rom had been released.

My precious

It's now been half a week since I got it, so far I bricked it more times than I remember but due to the avid Android community it's very easy to get it back on it's feet. :)
Today I have also just released my first app related to the device to help with some of the bricking. As it was very easy to brick but somewhat elongated to fix. The app simplifies it all and speeds it along.

Well that's it for today. :)

DxMs 100 Downloads !!!! Whooop =D

2010-08-13T12:18:00.000-07:00

To my surprise DxMs has hit over 100 downloads in the last few days. Hopefully those numbers shall continue to rise as I also hope to improve the program as I port it over to Python 2.7 to help improve the UI. :)

Arduino and PacMan ....waka waka waka Part 1

2010-08-13T12:15:00.000-07:00

After much thought and bordem I decided to buy an Arduino micro controller as well as a few add-ons for it, i.e. RGB LED matrix and an ethernet sheild(add-on).
How powerful is this Arduino, ehh?
Well it's got an 8 bit 16mhz and 2Kbytes!!! of ram with a huuuuge 32kbytes of storage. So ok it's not the most powerful mini computer in the world, but it's good at what it does, interfacing to the real world.

My lil' Arduino on my lil' hand.

Once it arrive and I unpacked it from it's tiny box, I soon realised I had ~~somehow dropped~~ jumped into the deep end of having to learn how to code in C from scratch. So straight away the LED matrix and ethernet controller looked impossible.

After a good bit of learning (thanks arduino.cc), tinkering and experimenting I managed to get some LEDs blinking and soon I got the ball rolling.
Once I got the general syntax of the C language I could move on to bigger and brighter things, the Ethernet Sheild!!!!

Ethernet sheild

With this lil' add-on I can interface the arduino to a network and the internet, :).
So once again I went back to www.arduino.cc to figure out how to use this and soon enough I managed to get a webserver out of it :)
After having looked through a few more tutorials i decided to pick up a few more bits of ebay, a few LED bar graphs and so breadboard wires etc to see if I could make a few more simple devices before I tried to properly use the RGB LED matrix.

A light detector(LDR) attached to a LED bar graph

Summer Tinkerings - pyk8055, DxMs

2010-07-06T06:25:00.000-07:00

Summer's here ^.^
Been messing about with a few things and an old Velleman K8055 board. It allows me to connect and control inputs and outputs to various devices like lights, switches, fans etc from my computer.
The only problem was that all the documentation was for C based languages and there was only a dll to interact with.
So rather than trying to keep jumping in and out of the dll using ctypes all the time whilst programming, I decided to created a little module to do all the ctypes handling for me.
And pyk8055 was created.
Rest of the info and downloads are here:
https://sourceforge.net/projects/pyk8055/

My current ideas for the k8055 board are to try and wire it up to an old rc car radio and use the receiver to wirelessly control devices from my computer.

DxMs
---------

Over the last few months I either haven't had much time or been to lazy to develop DxMs so it was dead for a while. But now it's back!!
I improved the web player so that it now uses the official Divx Web player embed plugin.
There were a couple reasons why I did this:
- It looks sleeker than the old one.
- No stupid random weird unnecessary adverts.
- Easier to detect if the video is removed due to copyright issues.
The web player page also shows the synopsis of the film and any poster art available.

I also tweaked a few bits here and there to do with error handling and general smoothness of the program running.
At the moment I am trying to improve the kinda bad interface, as there were various problems with stretching of cells due to my still quite infant knowledge in python Tkinter programming. When I manage to create something which looks pretty reasonable and doesn't keep changing size whenever a new film is clicked I will then update the executable.
Until then use the source code or the old 0.3 executable .

Koolio :D

DxMs - Divx Movie streamer

2010-04-25T04:08:00.000-07:00

In all the free-time* I've had during the Easter break and so on, boredom got the better of my and I decided to start a new project. DxMs is a solution to one of my personal problems, sometimes when I have been bored and have wanted to watch a streaming movie/film I ponder around the web attempting to find a good film whilst trying to constantly dodge pop ups, adware and annoying adverts usually only to find a dead link. :(
So in an attempt to solve this I decided to try and create a program that would allow the user to choose a film to watch from a huge catalogue of films and then have it stream to either their default browser(with a customised page) or to a media player (VLC).

My goals/intentions are:

Create a user friendly GUI which gives the impression there are looking at their own local library of films rather than the web (Film info, pics).
Stop the user from having to view pop-ups and eliminate the risk of adware etc. Done through custom web-page creation and local media player.
Dynamically create/update a catalogue of films from Web resources (currently Divxfest.com[indexing site])
Make it open-source i.e. free to use and edit :).

These are my current starting goals which I would be content with if completed, once done I would like to try and add other resources and services to it i.e. other video sites(tv-shows, youtube, iplayer) as well as maybe some sort of recommendation service based on what the user has watched.

To help document and control its development I have created a Sourceforge page and utilised its SVN (Subversion) control, allowing for easy and centralised storage, back-up and sharing of source-code and other files.

But for the time being i.e. the next three weeks I will be putting its development on the back-burner whilst I try and pass first year at Uni. :)

*Time in which I should be studying and not procrastinating :)

GusNet app Downloader - Batch Scripting

2010-01-03T08:23:00.000-08:00

After having used linux package manager for some time and messed about with a site called Ninite (both of which are great), I decided to try and see if I could create my own minimalistic windows version using batch scripting.
Through a couple hours of research and work, I produced a fairly dynamic and easy to use application downloader.
It works by downloading two text files off on my dropbox fileshare, one which holds web addresses of all the applications and the other which holds names of those applications. It compiles these into a list and gives the user the choice of what to download.
I can easily add to the available applications by merely adding the new application web address and name to the two text files. Easy and Very expandable.
:)
Here are the downloads:
All in one file: GusNet App Downloader
GusNet App Downloader
!!!Requires!!!! WGET.exe (must be in same folder)

Sin graph generator and Pendulum program

2009-12-07T14:29:00.000-08:00

For part of my course one of our tasks for the week was to create and solve a problem (I created a sine graph) and then take someone else's problem and solve it. I was given the problem of creating a pendulum and simulating it swinging from horizontal to vertical (roughly).

Sine Graph
.Exe Setup:
Download
Source file (Must have Canvas module file in same folder to work):
Download

Pendulum
.Exe Setup:
(coming soon)
Source file:
Download

First Program - Sharp Edgez Music Streamer

2009-12-06T14:59:00.000-08:00

My first program post which isn't even in python but instead in good old Visual Basic.
Sharp Edgez showed me his new internet radio stream, was quite bored at the time and thought lets try and make a stand alone player (didn't help the website looked like crap).

And there you have it one very quick and minimalist program.
:)

Download

Welcome to the Py Hole

2009-12-06T11:54:00.000-08:00

After much thought (and through having seen a friends blog - J-dan) I decided to create this space for me to keep track of all my ongoing (mostly python) projects and stuff as well as random bits and bobs.