3.6 Bluetooth® Low Energy Peripheral Connection

This section helps users enable advertisements and connection on the Curiosity board using the MCC. The peripheral device will be the Curiosity board and the central device can either be a smart phone with a Light Blue app or another Curiosity board. BLE Advertising is broadcasting small packets to peer devices. In BLE, a peripheral device always starts with advertisements. Advertisement packets enable a central or observer to discover and connect to a peripheral.

Users can either choose to run the precompiled application example .hex file on the Curiosity board and experience the demo or can go through the steps involved in developing this application from scratch.

It is recommended to follow the examples in order, by learning the basic concepts first and then progressing to the more advanced topics.

Recommended Reading

  1. BLE Software Specification
  2. Getting Started with WME Bluetooth Low Energy Applications
Note: Refer to the Getting Started with WME Bluetooth Low Energy Applications from Related Links

Hardware Required

Table 3-11.  Hardware Required
ToolQty
Curiosity Board1
Micro USB cable1
Android/iOS Smartphone1

Software Requirement

  • MPLAB X IPE: For programming the precompiled hex file.
  • MPLAB X IDE: For programming the application example.
  • Teraterm: Terminal Emulator for displaying UART output.

Programming the Precompiled Hex File or Application Example

Programming the .hex File using MPLAB X IPE

  1. Precompiled .hex files are located in “<Harmony Content Path>wireless_apps_ble\apps\peripheral_conn\hex\ “ folder.
  2. For more information on the programming steps, refer to the Programming a Device in MPLAB IPE.
    Note: Users must choose the correct device and tool information.

Programming the Application using MPLAB X IDE

  1. Follow the steps mentioned in Running a Precompiled Example
  2. Open and program the application example “peripheral_conn_xxxx.X” where xxxx refer to device (for example: WBZ451, project file: peripheral_conn_wbz451.X) located in “<Harmony Content Path>\wireless_apps_ble\apps\peripheral_conn\firmware” using MPLAB X IDE .

For more details on finding the Harmony content path, refer to Installing the MCC Plugin.

Demonstration

Developing the Application from Scratch using MCC

This section explains the steps required by a user to develop this application example from scratch using MCC
Note: It is recommended that new users of MCC to go through the MPLAB® Code Configurator (MCC) User's Guide.
  1. Create a new MCC Harmony Project by selecting the device. For more details, refer to Creating a New MCC Harmony Project.
  2. Launch the MCC from the toolbar as illustrated below. The project graph will open with the default components.
    Figure 3-67. MCC
  3. In the Device Resources window, expand Libraries > Harmony > Wireless > Application Services. Then, click the Plus Symbol to add the BLE Config App Service Component to the project
    Figure 3-68. BLE Config App Service
  4. All BLE Stack related components will be added into the project graph. Accept dependencies or satisfiers by selecting Yes.
  5. For configuring BLE Config App Service component based on the device refer to Adding BLE Config App Service Component to Project Graph and Selecting the Device in Getting Started with WME Bluetooth Low Energy Applications from Related Links.
  6. To enable digital and communication interfaces, refer to Enabling Digital Input/Output and Communication Interfaces Through System Hardware Definition (SHD) component in Getting Started with WME Bluetooth Low Energy Applications from Related Links.
  7. For FreeRTOS component settings refer to the Configuring FreeRTOS in Getting Started with WME Bluetooth Low Energy Applications from Related Links.
  8. For WBZ451
    1. Verify if the project graph window has all the expected components, as illustrated in the following figure:
      Figure 3-69 3-71. Project Graph
  9. For WBZ351
    1. Change FreeRTOS Component setting as illustrated in the following figure
      Figure 3-70. FreeRTOS Component
    2. Verify if the project graph window has all the expected components. as illustrated in the following figure:
      Figure 3-69 3-71. Project Graph
  10. Change BLE Stack Component configuration as illustrated in the following figure.
    Figure 3-72. BLE Stack
    Figure 3-73. BLE Stack

Generating a Code

For more details on code generation, refer to the MPLAB Code Configurator (MCC) Code Generation.

Files Containing User Application Code

Source code for the application will be generated from the MCC interface by clicking on Generate Code. User can add or edit the code in the highlighted files as illustrated in the following figure.
Figure 3-74. Files
Details on files that user can modify
Table 3-12. Source Files
Source FilesUsage
app.cApplication State machine, includes calls for Initialization of all BLE stack (GAP,GATT, SMP, L2CAP) related component configurations
app_ble_callbacks.cAll the event functions related to GAP, GATT, SMP and L2CAP events that user can use or modify .
app_utility.cContains generic utility functions that serve the purpose of providing reusable, common functionalities that can be applied across various parts of a program.
Note: app.c is auto generated and has a state machine based application code sample. Users can use this template to develop their application. Main application logic is implemented in void APP_Tasks() function.
Figure 3-75. app.c
Figure 3-76. app.c

References

  • Bluetooth Low Energy Peripheral Connection Application for: WBZ451
  • Bluetooth Low Energy Peripheral Connection Application for: WBZ351