> > RFID is pretty neat. I designed a cow thermometer (for 
> veterinarians) 
> > that logs the cow ID (read from an RFID tag), the cow's 
> temperature, 
> > the date and time. Thousands of readings can then be 
> downloaded later 
> > for analysis and archive. Prior to this, the typical logging system 
> > consisted of writing the date and temperature in chalk on 
> the side of the cow...
> 
> Is there a low-quantity way (low production numbers) to use 
> an RFID to read the state of a switch, i.e. no battery at the 
> "sender" at the switch? Range would have to be something like 
> a meter, reliability rather good.
> 
> Gerhard


I've seen modules that can do that.  They either have an on/off switch (ie
the module transmits its ID or it doesn't), or a few inputs where that data
gets encoded into the stream, which is more like what you want.

That was a few years back, and a quick Google didn't turn up anything.

Tony

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist