CC2540

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Revision as of 10:53, 16 November 2016 by Bertrik Sikken (talk | contribs)
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Project CC2540
Cc2540 webee.png
Making the CC2540 BLE dongle work
Status Initializing
Contact bertrik
Last Update 2016-11-16

Introduction

This page is about the CC2540 bluetooth low-energy sniffer dongle and getting it to work with Linux. A nice end result could be that it becomes possible to sniff directly in WireShark with this dongle.

I have such a "WeBee" dongle that can be found for about E15,- on websites like Aliexpress.

Analysis

USB descriptor

When plugging this stick into a Linux machine, you can see it uses only one bulk endpoint.

XXX

USB logs from Windows

This USB device does actually work with Windows:

I've captured a log of the communication over USB while the BLE is capturing bluetooth traffic from some iBeacon:

  • TODO

In the logs, I cannot see any firmware blobs being downloaded to the stick. Probably the stick comes with a pre-loaded firmware of itself to do the BLE sniffing.

Protocol

Cc2540 settings.png
Cc2540 packet details.png
Cc2540 wireshark.png

In the windows sniffer software, it seems there are only two things communicated:

  • towards the stick: which radio channel to sniff, and some other radio settings
  • from the stick: raw sniffed BLE frames

I can see a lot of similarities between the USB log and the BLE sniffer log. The bulk USB data starts off with two bytes indicating the length of the rest of the data.