FPGA’s can be very advanced to get started using, especially if you are used to microcontrollers.
But when you first get the right feeling and the proper mindset you will soon see the endless possibilities with the programmable logic.
One of the great aspects of the logic is the speed and the full control of what happens at every single clock cycle.
With this full control it doesn’t takes many lines of code to generate a very time-critical signal such as a video signal.
In this short post I will walk thru our current test setup with an FPGA, the Spartan 3E, controlling a 18-bit 7″ 800×480 TFT display.
I have for a long time been interrested in Kalman filers and how they work, I also used a Kalman filter for my Balancing robot, but I never explained how it actually was implemented. Actually I had never taken the time to sit down with a pen and a piece of paper and try to do the math by myself, so I actually did not know how it was implemented.
It turned out to be a good thing, as I actually discovered a mistake in the original code, but I will get back to that later.
I actually wrote about the Kalman filter as my master assignment in high school back in December 2011. But I only used the Kalman filter to calculate the true voltage of a DC signal modulated by known Gaussian white noise. My assignment can be found in the following zip file: http://www.tkjelectronics.dk/uploads/Kalman_SRP.zip. It is in danish, but you can properly use google translate to translate some of it. If you got any specific questions regarding the assignment, then ask in the comments below.
Okay, but back to the subject. As I sad I had never taken the time to sit down and do the math regarding the Kalman filter based on an accelerometer and a gyroscope. It was not as hard as I expected, but I must confess that I still have not studied the deeper theory behind, on why it actually works. But for me, and most people out there, I am more interrested in implementing the filter, than in the deeper theory behind and why the equations works. Read more…
We have been working with the new Raspberry Pi board for a while but didn’t show it to you guys before now.
Many of you might already have seen and read plenty of videos and articles about it so I thought it would be more appropriate to make a tutorial on how to use the GPIO’s, and especially on how to speed up the GPIO’s.
In this video I walk you thru all the steps from installing the Raspbian image which is based upon Debian. This is by far the most complete and well working image I’ve discovered.
Together with a complete X-window system it also comes with many different developer tools preinstalled such as Python and GCC.
So go watch the video while to set up your own Raspberry Pi for GPIO control.
I have been watching different videos of QuadCopters recently and I’ve been pretty amused. The way they fly and the way they control their movements is unbelievable – it almost looks like a bug.
If you don’t know what a QuadCopter is you should have a look at this video where he shows his homebuilt QuadCopter and his acrobatic skills with it.
So I decided to start reading some more about the materials behind these QuadCopters and how they manage to stabilize in the air.
In this blog post I will try to describe the different steps I have been thru to plan, design and build the prototype of my QuadCopter. There will be coming some more blog posts later on describing how to get the QuadCopter running, programming it, tuning it etc.
I have previous thought about buying a universal remote like this one, as I was tired of grabbing my JVC remote for my stereo everytime I had to turn it on, off or turn the volume up or down. But then I discovered Ken Shirriff’s IR Library for the Arduino. Normally the library didn’t support neither the Panasonic or JVC protocol, but I discovered that somebody else had already added them. See the forked github library. At first I simple downloaded the library and tested whenever it could decode the Panasonic protocol and send commands to my JVC stereo. It had to tweak the library a bit, but then it worked just fine.
I thought it would be a bit overkill to use an Arduino and I didn’t want to rewrite the whole library, so I decided to use another AVR’s but in a much smaller package, the ATtiny85. Which is 8-pin AVR. Read more…
NB: The newest source code can now be found at github.
As you might have seen, I finally got the PS3 Controller working via Bluetooth. Before you read any further, you should read my previous post first and also see the wiki for more information. Read more…
NB: The newest source code can now be found at github.
As Thomas origanally posted, the FEZ Panda can actually be used as a USB-Host: Fez Panda And USB Host. I have for long time wanted to use my PS3 DualShock 3 controllers for something useful (besides playing Playstation of course), therefore I thought it would be interesting to connect it to the FEZ Panda.
I recently bought the “Graphic LCD Serial Backpack” from Sparkfun. When reading the comments for the product. I discovered that a user named “SummoningDark”, had made a new improved firmware. A lot of people asked Sparkfun to change the official firmware with the new one, so i decided to check it out. The problem were that I do not own a programmer, so at first I thought that I had to buy one. But after some googling I found out that the Arduino could actually be used as an In System Programmer (ISP).
After a lot of work I finally got it working and it has really improved the perfomance of the screen. The speed is much higher (SummoningDark says 10 times) and there are no more bugs (with the old firmware the screen would suddenly write the text or a line a odd place).
I will now try to explain as best as I can, how to upload the new firmware.
NB: You can also use this guide if you need a different bootloader or another hex file on any AVR. This is just meant as an example. Read more…
I recently made a NXT motor shield for my arduino. It can control two NXT motors and also read the onboard encoders. In true Arduino spirit I decided to share it with the rest of the community. But first i will talk about how everything works, and then show the finished shield including a short video demonstration. Read more…
