Saturday, September 4, 2010

The Case of the Bus Pirate

I returned back from the USA, and amongst other things , I got myself the Bus Pirate.

Here is what it looks like

What is it? Its a bus sniffer.It can sniff and execute arbitrary commands over buses like I2C and SPI, making prototyping very easy.

In itself it is very fragile, and needs some protective covering so that it does not fling all over the place. I saw a few laser cut acrylic cases on the web, and decided to build my own.This is how it looks

Here is a quick guide to building one, and I will post an instructable soon

1) Cut three rectangular pieces of acrylic of size 7.5 cms by 4.5 cms.The bus pirate is 5 cms by 3 cms. Match all edges, file them smooth, and while sandwiching them tight with a bench vise, drill four 3/16" holes at the corners.Make sure you keep enough space, at the edges, so that the acrylic remains intact at the edges.

2) Take the piece in the middle, and cut out a rectangular piece of the size of the bus pirate.

3) Take the topmost piece, and make rectangular slots at the places where the headers come out from the bus pirate.

4) Create slots where the USB mini connector attaches with the bus pirate.

At the end, you should have the three pieces looking like these.

5) You are almost done.Insert the screws in the holes you drilled at the corners, and then file the corners round.Then keep the bus pirate in the second piece and layer the third top piece over it, and tighten the screws.Make sure you do no crush any circuity while tightening the screws.

Here is the final result

Total cost of materials-Under 100 Rupees/$2.This took me about 4 hours to build, and it probably needs a lot more finishing, but it does the job very well.

Thursday, February 4, 2010

New Idea

The Klann Linkage.Will make one.Will make the second, the third, the fourth.Will join these four in mechanical harmony together, and create a walking beast...

Sunday, January 10, 2010

Flight Simulators

I have always been interested in flying actual airplanes remotely, and after being to the US, I ordered a foam plane called a Super Cub.After flying it, I realized that it is incredibly difficult to start flying an airplane right away.You need to be under the aegis of an experienced pilot to really learn how to fly.I could not find any good flying clubs around town, and it being winter, the winds were not on my side.After a lot of reading, I found that there are simulators which help you learn how to fly.They are priced at about $200 a piece, and as ever there are free options available.
How do they work? Here is what the blog post is about :)

1)You need to have either a 4 channel transmitter or above.I chose the Spektrum DX6i.This has port on which you connect a cable, and the transmitter emulates as a 4-Button, 4-Position Joystick.This cable costs around $14.
For the software, I used FMS.
The argument here is, this is still larger in cost than the pricey simulator, but in the simulator, I get a stupid dummy joystick(No transmitter), which simply is a box with 4 potentiometers, and an expensive software( the FMS is just about same in performance and appeal as the other).
Currently, I have not purchased the DX6i, but the Super Cub did come with its own 3 channel Tx, in reality, it has four channels...Hmm..Well I have hacked around an old joystick earlier, so it should not be a difficult task to do so now with the Super Cub's transmitter.Here are some snaps which confirm my idea.

Here is an image with the back cover removed.The 4 Yellow Boxes show the contacts of the potentiometers which I will use and emulate a 4 channel joystick on my computer.

I would need to solder some wires and make a nice hole in the transmitter, stick a port there, and attach a cable to my computer.Trouble is, my computer only has USB ports(I so hate the new laptops, they are not really hacker friendly).So would need some kind of a dongle there.

More in later posts!

Thursday, January 7, 2010

eZ430 Chronos Development Tool from TI

I just recieved a package from TI, which had the eZ430 Chronos Development Tool I ordered for Sree.Here are some previews and a quick video showing the accelerometer function.Enjoy!!!

In the image below, you can see from left to right, the bundled CD(which has the drivers as well as the control software for the access points), the eZ430 emulator (programmer as well, to add your own code to the watch), the watch itself, the RF access point(shown in photos further) and a nifty screwdriver to remove the back panel of the watch, In addition to these, there are a few screws(not shown in images) if you end up losing some.

Here is the video, that shows the accelerometer function.I was pretty excited, as this happens to be the first video, I would have uploaded for sharing.