hi!, i need to make wireless an analog sensor. I think i can do it with attiny and a cheap rf kit, it's possible?
I mean somethink like that:
it's possible? and if i need 3 or 4 sensors with their attyny85, i suppose i need only one RX, how i can differenciate receptions?
if i need 3 or 4 sensors with their attyny85, i suppose i need only one RX, how i can differenciate receptions?
Well, that's quite easy - it's called "packet" transmission - the basis of the Internet.
You aren't transmitting continuously - you certainly are not if running from batteries. Each (packet) transmission starts (and ends) with a "sync" (synchronisation) character and follows a certain pattern which includes the identity (number) of the transmitting module, a packet length descriptor and data in a certain format. The second last thing sent is a checksum of some sort (either simple count - inverted - or a CRC) and the last is another sync character (look up "bit-stuffing" to see how the sync can be different to all other data).
The only limitation here is that two transmitters may - not being able to detect each other's transmission - transmit at once. This will invalidate both packets, so you have to allow for that data loss somehow.