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What ER (Receive Error Count) really mean?

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Hi all,

I am evaluating XBee-PRO S3B RF module. I configured three modules as AP=1 mode. one is configured as Non-routing coordinator (XBee-C), the other two configured as non-routing module (XBee-E1, XBee-E2). Now I am simultaneously transmitting 40 packets from both XBee-E1 and XBee-E2 to XBee-C. after transmission, I read back the network diagnostic parameter. There is a parameter ER (Receive Error Count) which are 3 on XBee-E1, 5 on XBee-E2, and 2 on XBee-C. what is this number real meaning? The description says "Received Error Count. This count is incremented whenever a packet is received which contained integrity errors of some sort". does it mean XBee-E1/E2/C received packet contains error bit? what happen if ER is incremented? The module will retransmit?

Thanks in advance.
asked Oct 3, 2016 in DigiMesh Proprietary Mesh Networking by madokapeng New to the Community (1 point)

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This means received packet was not in expected format, may be partial data was missing or having unexpected values.

In such case, receiver module will discard those packets and will not acknowledge them. Since Ack packet will not be received, Transmitter will retry/re-transmit to deliver packet again and wait for Ack response.
answered Oct 4, 2016 by asgm Veteran of the Digi Community (1,408 points)
selected Oct 5, 2016 by madokapeng
Hi asgm,

thank you for your answer. It makes sense to me. However, I see a large number of ER on XBee-E1 which is transmitting packet to XBee-C. This means XBee-E1 received packet from XBee-C having unexpected values, and the error packet will be dropped. Those error packets that sent to XBee-E1 are ACk packets from XBee-C. am I right? If I am right, then XBee-C should retry/re-transmit those ACK packets to XBee-E1. Which parameter on XBee-C will tell me that XBee-C is attempt to retry/retransmit?

Thank you very much
Check '0x8B Transmit Status' API packet on Transmitter. It contains value of transmit retry count.
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