Bluetooth Low Energy (BLE) From Ground Up™

Explore Bluetooth low energy, a short-range, low-power technology for small data and long battery life. Compare BLE with Bluetooth classic and note the evolution from 4.0 to 5.0.

Explore the Bearly stack, comprising the application, host, and controller blocks, and learn how single-chip, two-chip, and three-chip configurations split these blocks across hardware to enable Bluetooth communication.

Explore the link layer’s roles in advertising, scanning, initiating and maintaining connections, its interface with the physical layer via HCI, and direct test mode for manufacturing and certification.

Explore how link layer packets in BLE consist of preamble, axis address, header, length, data, and CRC, and contrast advertising versus data packets.

Understand the host controller interface (hci) as the physical and logical bridge between host and controller, enabling command, event, and data transfers over transports like uart, usb, and sdio.

Discover how the L2CAP layer multiplexes multiple Bluetooth protocols into standard packets, enabling segmentation and reassembly, and supports the generic attribute profile and generic access profile.

Discover how Bluetooth Low Energy 5 boosts IoT with 2x speed via the 2M physical layer, 4x range, and eightfold advertising capacity via secondary advertising channels.

Learn how advertising states operate, with fixed intervals, data limits of 31 bytes primary and 254 bytes secondary, and how a central can request a second response from the peripheral.

Explore how passive vs. active scanning affects receiving advertisement data and scan response data, then learn the eight BLE advertising events, including connectable, scannable, directed, and undirected variants.

Broadcasting data is unacknowledged and not guaranteed to reach listeners, while a connection enables reliable bidirectional exchanges with adaptive frequency hopping and defined connection events.

Explore the differences between modes and procedures in BLE, including discoverable and connectable states, bondable versus non-bondable, and practical examples like broadcast and direct connection establishment.

Explore how the Bluetooth Low Energy attribute protocol defines server and client roles, exposes data through attributes, and uses 16-bit and 128-bit UUIDs with a base address.

Analyze attribute parts by examining value, handle, and permissions; value holds data up to 512 bytes, 16-bit handle addresses attribute, and permissions govern read, write, and notify operations.

Delve into the gatt framework, mapping attributes to services, characteristics, and descriptors within a server, and learn how handles, uuids, and properties enable reads, writes, and notifications.

The GAP service is a mandatory GATT service that all devices must implement. The device name and appearance characteristics expose the device name and a 16-bit appearance value.

Explore the BlueNRG-MS stack architecture, featuring a combined host and controller on one chip and an application layer on the board, communicating via the ACA and AICI APIs over SPI.

Analyze how the BLE hardware configuration code wires the system clock, the GPU, and the BLE middleware, including the def config and spy files, to enable the BLE stack.

Implement the mandatory gap service for a BLE peripheral by initializing HCI, configuring the public address, creating service and characteristic handles, and updating the device name and appearance characteristics.

Implement BLE advertising to make the device discoverable, using the complete local name and service parameters, and verify advertising data with a central app.

Learn to create a custom service and add it using the service function, including defining a 128-bit you id and initializing the service.

Learn how to create a custom GATT characteristic in a BLE service by defining a 128-bit UUID, setting properties like notify, configuring security, and adding it to the service.

Send data from a microcontroller to a mobile app over Bluetooth low energy by updating a characteristic, handling read requests, and streaming sensor data.

Create two services, health and weather, each with two characteristics: beats per minute and weight, and temperature and humidity, using distinct UUIDs and handles.

Implement multiple bluetooth low energy services and characteristics, including health and weather services, by copying uids and creating handles for services and characteristics.

Update and manage Bluetooth low energy characteristics across health and weather services by implementing update data functions for bpm, weight, temperature, and humidity, plus handling read requests.

Develop a BLE chat firmware by creating a service with TX and RX characteristics, enabling bidirectional data between the board and the central device, and configuring properties.

Develop a BLE chat firmware by processing rx and tx events: receive data into a buffer, update the chat service characteristic, and handle attribute modified and notification events.

Develop and test a BLE chat firmware by triggering data sending on a push button, handling button states, and writing and notifying characteristic data in a live BLE service.

Explore Bluetooth low energy security concepts, including authentication, authorization, integrity, confidentiality, and privacy, and cover pairing, bonding, encryption, and key distribution, plus attacks like passive eavesdropping and identity tracking.

Explore how Bluetooth Low Energy optimizes for ultra low power, becoming the lowest power wireless technology, unlike classic Bluetooth’s rising data rates, which supports long-lasting connections with low energy use.

Bluetooth Low Energy leverages the 2.4 gigahertz ISM band worldwide, offering license-free access and simple policies while delivering excellent power efficiency for long-lasting devices.

Choose and assemble the stm32f4 nucleo board with the XnucleoIDB05A ble module to enable ble capability, then locate local suppliers via Google.

Download and install STM32CubeMX, accept the license agreement, and complete email verification to start the setup. Install embedded software packages for the F4 MCU family and check for updates.

Install and verify the STM32CubeMX BLE package to generate initialization code for BLE firmware development, preparing for testing in the next lesson.

Install Keil uVision 5, follow the installation wizard, install startup files and pack files for STM32, TM4C, and Tiva C boards, and learn to use the device search and simulators.

Install more packs to test cortex a devices with a simulator and arm hardware, then open uvision v5 and install drivers for the sdn 32 and texas instrument boards.

Test CubeMX installation by creating a simple LED blink project, selecting the STM32F4 microcontroller, configuring PA5 as a GPIO output, and generating code for the Keil MDK-ARM environment.