Zigbit Module Communications Delay

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Hi,
I'm using two meshnetics modules running bitcloud 1.13.0 basically a peer to peer network. The development kit is set as the coordinator and is attached to a host PC. Data is being transferred in only one direction (router to coordinator). I'm trying to setup a demo for a customer who requires streaming data at 50Hz (5 data bytes) and I'm seeing a number of delays in the communications.

Approximately 20 messages transmit successfully and then there is a large delay anywhere from .75-1.25 seconds. The delay is there regardless of the transmission rate (1-100Hz) though it does get more frequent with the higher frequency.

I've verified that I'm waiting for a proper response from the module before transmitting the next message using a protocol analyzer. There aren't any error responses from the module just a long delay.

Is there something in the configuration that I'm missing or does anyone have some suggestions?
Thanks
Justin

This topic has a solution.
Last Edited: Fri. Oct 16, 2015 - 02:16 PM
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Is it possible that your application introduces this delay? Is this possible that frame is lost and retransmission is required and there is a delay for this?

Can you send sniffer logs in Daintree format (.dcf)?

NOTE: I no longer actively read this forum. Please ask your question on www.eevblog.com/forum if you want my answer.

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Thanks for the response.

I don't believe may application is adding the delays because I removed my application entirely and wrote a Labview vi that's sole purpose is to send and receive data. I used two development kits and measured the average and peak time between messages and the delays are still there.

It is possible that the frame is being lost and retransmitted, but the setup has two units ~2ft apart in fairly clean environment. If there is significant packet loss then it would basically be unusable in the field.

I don't have any way to convert my sniffer logs to .dcf format at the moment. I'm sniffing the uart comms to the module and can give them in .logicdata format or as a image but I that may not be all that useful. I'm looking to see what other sniffers are currently available in the office.
Thanks,
Justin

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I consider UART handling code a part of the application. What application you are using in the module? Are you sure there is no some kind of tricky buffering in side?

50 frames per second is sort of on the edge of being possible with ZigBee, so this kind of problems is expected. Sometimes it is possible to dolve them, but not always.

NOTE: I no longer actively read this forum. Please ask your question on www.eevblog.com/forum if you want my answer.