XBee S2C 2.4 module bad throughput


I use Two digimesh 2.4 modules (XA and XB) and they are connected two the same computer with XCTU software open.

Both module have their default configuration exept for the serial rate for XA it is 57600 bps and XB it is 115200 bps.

I execute a throughput test thanks to the throughput tools in XCTU and this is what i get.

In the digimesh specification the RF throughput given is 250kbps i understand that the serial link can be a limitation but i don’t understand why the throughput is so low.

Thanks in advance for your help

The 250K is not the throughput. It is the fixed RF data rate the radios talk at.

Thank you very much for your answer.
I understand that the 250 kbps is the RF rate but
what do i need to do to have the 96 kbps throughput as mention in the datasheet ?

Can you provide the link to the document you are referring to? I ask as that sounds more like the 802.15.4 throughput.

Yes of course,
here is the link : XBee/XBee-PRO S2C 802.15.4 RF Module User Guide

That is what I thought. That is for the IEEE 802.15.4 firmware option and not the Digi Mesh version.

Ok, so what will be the maximum throughput value that the XB24C Digimesh 2.4 module can reach ?

I would expect it to be abut 33 to 38kbps.

Even for a serial datarate of 115200 bps in transparent mode ?

Yes. That is simply because the throughput is a limit of the Mesh protocol.

Is it possible to tell me where to find this in the documentation ?

I also noticed that in transparent mode when we increase the payload size during throughpu test we also increase the throughput.
I don"t understant why increasing the payload also increase throughput.

I don’t know why it is not in the Manual for the XBee 3 but it is listed at XBee S2C DigiMesh 2.4 User Guide

I succeed to have 45 kbps increasing the payload and set TO register to C1.
serial rate is set to 57.6 kbps.

In 115.2 kbps i can go up to 80 kbps but throughput periodically falls to 0.

So i think we can go higher than 32 kbps