Active scan stuck without sending status response

XBee & XBee Gateway XBee - Zigbee
1

Hello,
I’m having problem when sending the active scan AT command from the end node device.

Setup:
1 Digi devkit configured as coordinator with an infinite node join time with an Extended PAN ID = 1122334455667788
1 Digi devkit configured as end node with an Extended PAN ID = 0

Modules:
Product: XB3-24, Function: Digi XBee3 Zigbee 3.0, Firmware 1013.

Software:
XCTU application version 6.5.13.

Procedure:

  1. I’m waiting for association indication.
  2. Send Active scan command using XCTU “7E 00 04 08 01 41 53 62”

Results:
According to my setup I should receive these answers from the module.

  • Scan result “7E 00 15 88 01 41 53 00 02 10 AF 9F 11 22 33 44 55 66 77 88 01 00 FF F0 2E”
  • Scan status “7E 00 05 88 01 41 53 00 E2”

When issuing the active scan command, someties I do not received the scan status. Sometimes the module does not send any scan result and scan status.

Do you have any idea of the cause of this issue ?

Best Regards,
Eric

2

Which module are you trying to perform the Active Scan from? The coordinator or end device?

4

Hi,
I’m doing the active scan from the end node module.

5

In the Zigbee standard, it is not the End device that preforms an Active Scan but it is the Coordinator that would.

6

It is possible for an end device to perform active scan. Check the link below.

https://www.digi.com/resources/documentation/Digidocs/90002002/Default.htm#Concepts/c_zb_discover_end_devices.htm

7

I think there is some confusion. Yes, the Routers and End Devices do preform an Active Scan to Join an Existing network. But you do not control that function. You do not have the ability to have a Router or End device manually preform an Active Scan to see what other networks are in range. That is, you would need to be able to turn off the capabilities of the Router or End device to Join a network. That is not a function you can do.

You can only turn off Joining on an Existing Network or on a Node once it has joined a network (NJ).

8

Sorry for the confusion. Basically I want my end node to find the coordinator, which is always joinable. I’m sending the “AS” AT command from my end node device. Most of the time I received the coordinator PAN ID but sometimes I do not received any response from the “AS” command. This is I described in my original post. Thanks.

9

By default, an end device is always trying to Join any network that is on the same PAN ID and Channel mask that is allowing Joining. You do not have the ability to turn off joining.

To do what you want, you would need to Turn off Joining first.

Before a device is associated to a network (AI != 0), it will continuously perform an active scan in the background, searching for a valid network to join. While this is occurring, you cannot manually perform an active scan using the AS command. You can bypass this restriction by setting DJ to 1. This will disable joining and halt the background active scans.

This is ONLY on the XBee 3 modules running the Zigbee function set.

10

Hi, Just to add more info on my problem. The behavior I’ve observed is less reproductible with the firmware version 1010.

Eric