Wednesday, January 04, 2012

First spin of the propeller

A new toy dropped through the letterbox today. It is a Gadget Gangster Propeller Platform USB demo board for experimenting with the Parallax Propeller microcontroller. If you haven't heard of the Parallax Propeller before then it is an inexpensive micro chip that contains eight processors called cogs (as in gear wheels) that can run independently in parallel. It's quite a bit different from the Microchip PIC or Atmel devices which have a single processor architecture similar to an ordinary computer.

 I sent off for the board just after Christmas, after reading about it in Eldon Brown WA0UWH's blog. Eldon posted code showing how the board could be used as a QRSS beacon. I was quite excited by the idea of a device that with simple programs even I could understand could be made to emit RF.

I sent off for the board on 27th December choosing the low cost untracked USPS air mail shipping option and it arrived today, 4 January - much quicker than expected. What's more, there were no nasty customs charges! Gadget Gangster still has a special offer of $10 off for the board, so if you fancy getting one of these to play with now is the time to do something about it.

I was very impressed at the speed with which Gadget Gangster processed my order. What you get, though, is just the board. You will need to provide a power supply (7.5 - 12V with a 2.1mm barrel connector, centre positive) and a USB cable with a mini-USB jack at one end. These seem to breed in my junk box so that was not a problem. You will also find useful a small breadboard and some hookup wire to attach components to the board and test your programs.

I installed the Propeller Tool - a free download from the Parallax website, connected the board to my Samsung NC10 netbook. I then tried the Blinky Light tutorial from the Gadget Gangster site. It didn't work - until I connected the LED the correct way round (stupid newbie error!)

Over the next few days I'll be working through the tutorials to get the hang of the system. Then I'll take a look at Eldon's QRSS beacon code and adapt it to send my own call. I'd like to make a WSPR beacon. I don't know yet if that will be possible, but I'm looking forward to playing with this Propeller chip and using it in some radio-related project. Watch this space!

3 comments:

Eldon R. Brown SR said...

Julian,

I am happy that my project and the Propeller holds your attention and provides distraction from your life's other issues. I always enjoy reading of your projects and reviews.

Eldon - WA0UWH

G4FUI said...

Strangely, I've now learned of TWO of these kind of devices in the same week. Firstly an "Arduino Uno" board, one of which I have ordered from a UK supplier, and now "your" Gadget Gangster Propeller, and those after having locked horns with those rather impentetrable (to me) PIC microcontrollers at the assembly code level. It's a small world!

As far as I can see, Arduino and Gadget Gangster seem to be doing similar things, mainly making microcontrollers a bit more "user-friendly" and allowing the limiting factor to be the user's imagination rather than the esoterica associated with W and F registers, etc, etc.

Julian Moss said...

I've never looked at the Arduino. The Propeller seems to be a lot more powerful than the Microchip PICs, but main thing is the Spin programming language which is much higher level and easy to understand compared to PIC assembler. In my younger days at university I was a bit of an assembly code wizard but my 58 year old lobotomized brain can't hack it at all now.