Four things you should know about the upcoming Bluetooth World 2017 event
I just wanted to share four things I recently learned about the upcoming Bluetooth World 2017 event (March 28-29, 2017 in Santa Clara, California). This will be my first time attending the event, but from what I remember, last year the fee to attend was a bit on the high side (close to $1,000). This year,…
Read MoreUnderstanding SN and NESN in a BLE Link Layer packet
In my previous video looking at connection data captured via a BLE sniffer, I missed explaining two bits in the data that can be confusing to understand. The bits are the SN and NESN in the LL data packet. A few notes to better understand these bits: NESN and SN are used for data flow…
Read MoreHow do I choose a UUID for my custom services and characteristics?
First, a few things to know: “A UUID is a universally unique identifier that is guaranteed to be unique across all space and all time” (Bluetooth 4.2 spec, Vol 3, Part B, section 2.5.1 UUID) A UUID is a 128-bit value. There are reserved UUIDs by the Bluetooth SIG that are generally represented by their 16-bit…
Read MoreWhat is the maximum size of data that can be encapsulated in a characteristic?
The answer: 512 bytes. But to understand where that came from, let’s first look at what a characteristic really is. Attributes are the generic term describing the smallest element in the Generic Attribute Profile (GATT). So each of Services, Characteristics, and Descriptors is actually an attribute, and according to the Bluetooth 4.2 spec (Volume 3,…
Read MoreThe best Bluetooth low energy sniffer tutorial (Connections)
A BLE sniffer can be very handy. 3 primary use cases come to mind: Debug problems with BLE connections Reverse engineer a BLE device Last but not least, as a way to learn about how BLE works and understand how data gets transferred between Central and Peripheral In the previous blog post and video on BLE…
Read MoreThe best Bluetooth low energy sniffer tutorial (Advertisement Data)
In the previous blog post, we went over the different BLE sniffers available in the market and compared the pros and cons of each. In this video below we walk through a live demo of capturing BLE advertisements using the TI CC2540 USB Dongle BLE sniffer. We look at the different aspects of the captured…
Read MoreHow to use a Bluetooth (BLE) sniffer without pulling your hair out!
How to use a Bluetooth Low Energy sniffer without pulling your hair out! While working on a client’s project it became necessary to use a Bluetooth Low Energy sniffer to debug some weird behavior happening with the data transfers between the master and slave device. I had read quite a bit about BLE sniffing before and talked…
Read MoreBLE connection intervals and events in under 5 minutes
Understand BLE connection intervals and events in under 5 minutes A BLE connection interval is the time between two data transfer events (BLE connection events) between the central and the peripheral device. The theoretical value ranges from 7.5 ms to 4 secs (with increments of 1.25 ms). A few notes regarding BLE connection intervals: The…
Read MoreThe Basics of Bluetooth Low Energy (BLE)
Bluetooth Low Energy (BLE) is a low power wireless technology used for connecting devices with each other. BLE operates in the 2.4 GHz ISM (Industrial, Scientific, and Medical) band, and is targeted towards applications that need to consume less power and may need to run on batteries for longer periods of time—months, and even years. Bluetooth started as a short-distance…
Read MoreAn honest review of Bluetooth Developer Studio (BDS)
What is Bluetooth Developer Studio? Bluetooth Developer Studio (BDS) was officially released by the Bluetooth SIG back in October 2015. It allows you to focus on the high-level design of your Bluetooth low energy devices, whether it’s a central or peripheral device. It offers a clean and simple interface where you can drag and drop profiles,…
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