CC2531EMK: APS Counter value is only 69 or 174

Terence Chan1

Part Number: CC2531EMK
Other Parts Discussed in Thread: PACKET-SNIFFER

Hello,

I have a query where the captured packets using SmartRF Packet Sniffer where under the APS layer, my APS counter is only either 69 or 174.

Shouldn't it be implemented as a counter that is incremented after each command?

Some commands are also indicated as broadcast when they are supposed to be unicast as compared to the results I've gotten using another sniffer with Wireshark

I have included my .psd file as attached.

CC2531EMK_061120_V2.psd

Regards,

Terence

over 5 years ago

0 Ryan Brown1 over 5 years ago

TI__Guru**** 223757 points

Hello Terence,

Simply put, the sniffer log shows the ZC (0x0000) using an APS Counter of 174 and the ZED (0xCACF) with an APS Counter of 69 consistently. This could be specific to your application, depending on the commands being used and whether you are incrementing seqNumber or not. It is not a requirement of the Zigbee Specification for this value to increment sequentially but you can notice that the MAC & NWK Sequence numbers are doing so as expected.

However, I would rely on Wireshark's interpretation which is more updated than the deprecated PACKET-SNIFFER software. In fact, when I load the sniffer log into Ubiqua I can see the APS Counter increasing incrementally as expected. This verifies that the Packet Sniffer Zigbee 2007 profile interpretation is insufficient to correctly parse Zigbee 3.0 packets.

Regards,
Ryan

0 Terence Chan1 over 5 years ago in reply to Ryan Brown1

Prodigy 120 points

Hi Ryan,

I am actually doing a sniff on my ZigBee devices which are not developed by me.

I just wanted to experiment things out to see the communications between the hub and the end device.

I didn't know that Ubiqua can open the .psd file. I tried opening it but I have a lot of lines/packets with "*** Unable to decrypt Data ***".

May I know how do I rectify this? I have already added the Zigbee Network Key in the "Preferences>Security" but am still facing this issue.

Regards,

Terence

0 Ryan Brown1 over 5 years ago in reply to Terence Chan1

TI__Guru**** 223757 points

The only difference I can think of is that I've added the global TC Link Key. Here are further instructions regarding the Ubiqua setup:

https://e2e.ti.com/support/wireless-connectivity/zigbee-and-thread/f/158/t/699648
https://dev.ti.com/tirex/content/simplelink_cc13x2_26x2_sdk_4_30_00_54/docs/zigbee/html/zigbee/packet_sniffer.html#running-the-packet-sniffer

Regards,
Ryan

0 Terence Chan1 over 5 years ago in reply to Ryan Brown1

Prodigy 120 points

Hi Ryan,

Seems weird as I did it the same as you but couldn't get it to work. But its okay as I used the Ubiqua to sniff instead and exported it to .pcap format, and then used Wireshark to view it.

Thank you!

Regards,

Terence

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CC2531EMK: APS Counter value is only 69 or 174