Welcome Guest,Register Now
Log In

ANT Forum

Welcome guest, please Login or Register

   

Daisy chain connection

Rank

Total Posts: 1

Joined 2014-06-09

PM

Hello,

We're currently looking for a RF protocol which can meet our requirements in one project.

We need to create sensors daisy chain network, where each device should act as a sensor and an realy at the same time. Each device should get measurement and forward data to the next device in the chain, we expect to have up to 30 nodes with 6m separation between the nodes.

All nodes should forward measurements to the main hub located at the end of the chain.

Is it possible to create such network using ANT protocol, does ANT have support for such connection?

I'd be appreciated for your help.

Best Regards,
Krzysztof Rosinski



     
Avatar
RankRankRankRank

Total Posts: 235

Joined 2012-08-31

PM

Hi Krix,

As described it sounds pretty straightforward to create that kind of network using ANT. I am assuming that each node only needs to communicate with the nodes around it, and not directly to the end hub. ANT's typical range is 10m.

How much data needs to be transmitted? ANT is a low data rate protocol, so this is worth checking. Each node transmitting 8 payload bytes @ 50 messages per second would be safe - above that you may need to use caution. Most typical ANT applications use channel periods below 10Hz.

However, assuming that's ok...

I would probably open a master channel on each node to transmit the data it has to send, and open a slave channel to receive from the device before it. There is no difficulty setting up ANT nodes as both master and slaves at the same time. Open a slave channel on the hub to receive from the last node in the chain.

Are your devices static or moving around? Do you have any power constraints? These would be the questions I would look at next to choose whether to use synchronous or asynchronous channels, and decide whether any handshaking would be needed. Presumably you will need to define a method for establishing and deconstructing the network as well. This could be as simple as 'every node connects on power up' if your network is fully defined in advance (i.e. all nodes are known).

If you'd like to find out more, I'd start here: http://www.thisisant.com/developer/ant-basics/ant-basics/#106_tab and here: http://www.thisisant.com/developer/ant-basics/advanced-features/

Hope that helps,

Kat