Propeller Communication

copacetic353

Hello all,

So I have yet to tinker with the Propeller yet, I will be buying a bunch of stuff in November and I am in the design phase for my next project. I want to get as many things figured out now so I can, so to say, hit the ground running.

I want my Propeller based system to be able to communicate with a ground station. It will be transmitting things like GPS locs, attitutude, and hopefully video. It would be nice to set up the system to recieve communications back for future development.

My questions:

What are the best ways for the Propeller to communicate wirelessly?
Should the Propeller be communicating with another Propeller or would a lesser powered microchip be sufficient?
Should there be two communication streams? One for video another for data?
How does communication via the Prop actually work?

Thanks for answering some n00b questions and some more advanced ones.

And, as always, thanks for your time!

Scott

SRLM

1) Depends on what your needs are. In general, the trade off is high bandwidth vs long distance. Then there are considerations such as networking and mesh technologies, or old school broadcast. Security may also be an issue.
2) Depends on the baud and what you want to do with the data.
3) Definitely. The Propeller can't handle video input even without wireless.
4) Bit banging is the method the prop uses. Take a look at FullDuplexSerial for the specifics of serial communication. Also available is SPI and parallel. Most wireless devices use serial though.

Mike Green

1) There is no "best way" for the Propeller to communicate wirelessly. It depends on what kind of range you need, your power budget, and what sort of data rate you need to support.

2) It's usually easier to have the same microcontroller on both ends. You could also have the Propeller talk directly with a PC on the ground if you want.

3) Yes, there should be two communications streams, one for data and the other for video.

4) Although the Prop can generate video and audio (listen to some of the vocal tract demonstrations, particularly the singing monks), usually it just produces a serial asynchronous communications channel. There are several I/O drivers that will take care of the details of transmitting and receiving standard 8-bit no-parity serial data at pretty much any speed that your communications gear can handle. The Propeller can function as a low speed modem over a wireless audio channel, but you can buy nice wireless links that take care of a lot of the work needed for a reliable communications channel. xBee is one example if the range is what you want.