ANT Forum

Hi All,

For my project I want to send stringified JSON-RPC objects to about 25 nodes with a mesh network. Say these messages are of size: "{address: hd7ahkvf, origin: hh27hd, UID: 22dgc, content: { id: 6654gd, method: "dosomething", params: {a:234, b:false, c:"bananas"} } }"

Will these strings be stripped down to chunks of a few characters per message over the channel? I could send it with burst but if all nodes are bursting data to eachother, say 4 times a second, this may be problematic (?).

I only have 2 nodes to test on (NRF51422 based N5 kits) so I'm unsure if this is feasible to scale up. Could anyone shed some light on this?

Regards,

Alex      

Hi Alex,

If you use a limited character set you can transmit each character using ASCII or UTF-8 with 1 byte per character. Your example string is ~125 characters / 8 => 16. So you're looking at 16 ANT messages (broadcast or acknowledged) or a 16 packet burst, (or two 8 packet bursts if you find that works better with your timing).

I would consider condensing the data if you can. For example if you know which parameters you will be transmitting in each burst, you can define which bytes you will transmit each parameter value in, and just transmit the value etc.

Take a look at the ANT basics section and watch the video so you understand how the ANT devices communicate. http://www.thisisant.com/developer/ant/ant-basics/

Hope that helps,

Kat