Hi,
New to the group... But did google around the archives first, so please excuse if this has been done to death - I did try(!)
I play with AVRs (Tiny/Mega) as a hobby (linux sysadmin, perl/C programmer by trade).
I fancy having a play with some radio datalinks (with a view to home automation) - but there seem to be a million modules and a fair number of frequencies and standards. I'm just after some pointers based off some simple requirements:
Important:
a) Range - 20m through masonry (11" brick wall and 4" wall sort of thing, no rebar), 40m free air (could accept 10/20m)
b) Usable data rate - 10's to 100-ish kbit/sec
c) Cheap - 20 pounds sterling give or take, say 40 US dollars for a small easy to mount module (wire pads/header pins - no funky surface mount modules, my soldering isn't that advanced)
Pie in the sky wish list
d) Ideally simple framing built in - ie I clock a bunch of data in and hit "send" so to speak, and it transmits. Receive buffers frame and wiggles an interrupt. "Frame" could mean 8 bit word, or entire long packet (100's words).
But ultimately I *could* live with wiggling some pins on a simple RF module where the 2 pins send different signals over the carrier to indicate 1 and 0.
d) would be nice as it simplifies programming by miles, but not if it impacts on c)
Not too bothered whether 433MHz, 868MHz, or 2.4GHz (this is the UK BTW), though I suspect 868MHz would be slightly better being less crowded.
Zigbee looked interesting but I don't really need a whole protocol stack (I can do that) and it's not cheap.
Any pointers as to any technogolgies or modules that would be worth looking at would be most gratefully received. I've looked - wood and trees syndrome - don't know how to filter the choices down...
Ta muchly :)
Tim