Is it possible to use more than one transmitter with one single receiver? I want to collect data from different sensors into one main controller.
The data transmit period will be around once a minute, is there a library that supports sequential data transmit?
Thanks
With those very cheap receivers and transmitters ?
The VirtualWire library goes well with those.
http://www.airspayce.com/mikem/arduino/VirtualWire/
If two transmitters interfere, nothing is received, since the VirtualWire has a checksum.
Looks like I need to come up with a custom library to control communication and sequence of data sending. These are cheap and can be used easily, that is a big pros. But sequencing the communication is a tough matter.
How about nrf24l01 rf units? Can I use them for the same idea (1 receiver, multiple transmitter)?
What do you mean by sequencing ?
A custom library ? No one can beat the VirtualWire library.
The simple remote light switches (that also use the 433MHz) send the message a few times (maybe 10 or 20 times).
The VirtualWire library sends it just once, but you can add an extra layer.
For sending the temperature and humidity to a central unit, those modules can be used. I use a random delay between sending the packages, to prevent that multiple transmissions occur at the same time.
The XBee modules are able to do more, but are more expensive.
The Arduino can store data in EEPROM. So you could store some data and re-transmit it later.
If you use a transceiver such as nrf24l01 then the master can poll all the slaves and prevent data interference:
master: unit 1 send
unit 1: 1 here, data
master: unit 2 send
unit 2: 2 here, data
master: unit 3, send
unit 3: (no response
master can re-request, or declare a comm failure with unit 3
continuing:
master: unit 4, send
unit 4: 4 here, data