This code example demonstrates the implementation of a Bluetooth® LE custom service with Bluetooth® security using AIROC™ CYW20829/CYW89829, PSoC™ 6, and ModusToolbox™ environment.
Provide feedback on this code example.
- ModusToolbox™ v3.2 or later (tested with v3.3)
- Board support package (BSP) minimum required version for :
- PSoC™ 6 MCU: v5.0.0
- XMC7000 MCU: v2.3.0
- CY8CKIT-062-BLE/CY8CPROTO-063-BLE/CYBLE-416045-EVAL : v4.0.0
- CYW920829M2EVK-02/CYW989829M2EVB-01/CYW989829M2EVB-03 : v2.0.0
- Programming language: C
- Associated parts: All XMC7000 MCU and AIROC™ CYW20829 Bluetooth® LE SoC, PSoC™ 6 MCU with AIROC™ Bluetooth® LE
- GNU Arm® Embedded Compiler v11.3.1 (
GCC_ARM) - Default value ofTOOLCHAIN - Arm® Compiler v6.22 (
ARM) - IAR C/C++ Compiler v9.50.2 (
IAR)
- AIROC™ CYW20829 Bluetooth® LE Evaluation Kit (
CYW920829M2EVK-02) – Default value ofTARGET - AIROC™ CYW89829 Bluetooth® LE Evaluation Kit (
CYW989829M2EVB-01,CYW989829M2EVB-03) - PSoC™ 6 Wi-Fi Bluetooth® Prototyping Kit (
CY8CPROTO-062-4343W) - PSoC™ 6 Wi-Fi Bluetooth® Pioneer Kit (
CY8CKIT-062-WIFI-BT) - PSoC™ 62S2 Wi-Fi Bluetooth® Pioneer Kit (
CY8CKIT-062S2-43012,CY8CEVAL-062S2-CYW955513SDM2WLIPA) - PSoC™ 62S1 Wi-Fi Bluetooth® Pioneer Kit (
CYW9P62S1-43438EVB-01) - PSoC™ 62S1 Wi-Fi Bluetooth® Pioneer Kit (
CYW9P62S1-43012EVB-01) - PSoC™ 62S3 Wi-Fi Bluetooth® Prototyping Kit (
CY8CPROTO-062S3-4343W) - PSoC™ 62S2 Evaluation Kit (
CY8CEVAL-062S2,CY8CEVAL-062S2-LAI-4373M2,CY8CEVAL-062S2-LAI-43439M2,CY8CEVAL-062S2-MUR-4373EM2,CY8CEVAL-062S2-MUR-4373M2,CY8CEVAL-062S2-CYW43022CUB) - PSoC™ 6 Bluetooth® LE Pioneer Kit (
CY8CKIT-062-BLE) - PSoC™ 6 Bluetooth® LE Prototyping Kit (
CY8CPROTO-063-BLE) - EZ-BLE Arduino Evaluation Board (
CYBLE-416045-EVAL) - PSoC™ 62S2 Wi-Fi Bluetooth® Prototyping Kit (
CY8CPROTO-062S2-43439) - PSoC™ 6 AI Evaluation Kit (
CY8CKIT-062S2-AI) - XMC7200 Evaluation Kit (
KIT_XMC72_EVK_MUR_43439M2)
This example uses the board's default configuration. See the kit user guide to ensure that the board is configured correctly.
Note: The PSoC™ 6 Bluetooth® LE Pioneer Kit (CY8CKIT-062-BLE) and the PSoC™ 6 Wi-Fi Bluetooth® Pioneer Kit (CY8CKIT-062-WIFI-BT) ship with KitProg2 installed. ModusToolbox™ requires KitProg3. Before using this code example, make sure that the board is upgraded to KitProg3. The tool and instructions are available in the Firmware Loader GitHub repository. If you do not upgrade, you will see an error like "unable to find CMSIS-DAP device" or "KitProg firmware is out of date".
Note: The AIROC™ CYW20829 Bluetooth® Kit (CYW920829M2EVK-02) ships with KitProg3 version 2.21 installed. The ModusToolbox™ requires KitProg3 with latest version 2.40. Before using this code example, make sure that the board is upgraded to KitProg3. The tool and instructions are available in the Firmware Loader GitHub repository. If you do not upgrade, you will see an error such as "unable to find CMSIS-DAP device" or "KitProg firmware is out of date".
Download and install the AIROC™ Bluetooth® Connect App for iOS or Android.
Scan the following QR codes from your mobile phone to download the AIROC™ Bluetooth® Connect App.
Install a terminal emulator if you don't have one. Instructions in this document use Tera Term.
The ModusToolbox™ tools package provides the Project Creator as both a GUI tool and a command line tool.
Use Project Creator GUI
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Open the Project Creator GUI tool.
There are several ways to do this, including launching it from the dashboard or from inside the Eclipse IDE for ModusToolbox™. For more details, see the Project Creator user guide (locally available at {ModusToolbox™ install directory}/tools_{version}/project-creator/docs/project-creator.pdf).
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On the Choose Board Support Package (BSP) page, select a kit supported by this code example. See Supported kits.
Note: To use this code example for a kit not listed here, you may need to update the source files. If the kit does not have the required resources, the application may not work.
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On the Select Application page:
a. Select the Applications(s) Root Path and the Target IDE.
Note: Depending on how you open the Project Creator tool, these fields may be pre-selected for you.
b. Select this code example from the list by enabling its check box.
Note: You can narrow the list of displayed examples by typing in the filter box.
c. (Optional) Change the suggested New Application Name and New BSP Name.
d. Click Create to complete the application creation process.
Use Project Creator CLI
The 'project-creator-cli' tool can be used to create applications from a CLI terminal or from within batch files or shell scripts. This tool is available in the {ModusToolbox™ install directory}/tools_{version}/project-creator/ directory.
Use a CLI terminal to invoke the 'project-creator-cli' tool. On Windows, use the command line 'modus-shell' program provided in the ModusToolbox™ installation instead of a standard Windows command-line application. This shell provides access to all ModusToolbox™ tools. You can access it by typing "modus-shell" in the search box in the Windows menu. In Linux and macOS, you can use any terminal application.
The following example clones the "hello sensor" application with the desired name "HelloSensor" configured for the CY8CKIT-062-WIFI-BT BSP into the specified working directory, C:/mtb_projects:
project-creator-cli --board-id CY8CKIT-062-WIFI-BT --app-id mtb-example-btstack-freertos-hello-sensor --user-app-name HelloSensor --target-dir "C:/mtb_projects"
The 'project-creator-cli' tool has the following arguments:
| Argument | Description | Required/optional |
|---|---|---|
--board-id |
Defined in the field of the BSP manifest | Required |
--app-id |
Defined in the field of the CE manifest | Required |
--target-dir |
Specify the directory in which the application is to be created if you prefer not to use the default current working directory | Optional |
--user-app-name |
Specify the name of the application if you prefer to have a name other than the example's default name | Optional |
Note: The project-creator-cli tool uses the
git cloneandmake getlibscommands to fetch the repository and import the required libraries. For details, see the "Project creator tools" section of the ModusToolbox™ tools package user guide (locally available at {ModusToolbox™ install directory}/docs_{version}/mtb_user_guide.pdf).
After the project has been created, you can open it in your preferred development environment.
Eclipse IDE
If you opened the Project Creator tool from the included Eclipse IDE, the project will open in Eclipse automatically.
For more details, see the Eclipse IDE for ModusToolbox™ user guide (locally available at {ModusToolbox™ install directory}/docs_{version}/mt_ide_user_guide.pdf).
Visual Studio (VS) Code
Launch VS Code manually, and then open the generated {project-name}.code-workspace file located in the project directory.
For more details, see the Visual Studio Code for ModusToolbox™ user guide (locally available at {ModusToolbox™ install directory}/docs_{version}/mt_vscode_user_guide.pdf).
Keil µVision
Double-click the generated {project-name}.cprj file to launch the Keil µVision IDE.
For more details, see the Keil µVision for ModusToolbox™ user guide (locally available at {ModusToolbox™ install directory}/docs_{version}/mt_uvision_user_guide.pdf).
IAR Embedded Workbench
Open IAR Embedded Workbench manually, and create a new project. Then select the generated {project-name}.ipcf file located in the project directory.
For more details, see the IAR Embedded Workbench for ModusToolbox™ user guide (locally available at {ModusToolbox™ install directory}/docs_{version}/mt_iar_user_guide.pdf).
Command line
If you prefer to use the CLI, open the appropriate terminal, and navigate to the project directory. On Windows, use the command-line 'modus-shell' program; on Linux and macOS, you can use any terminal application. From there, you can run various make commands.
For more details, see the ModusToolbox™ tools package user guide (locally available at {ModusToolbox™ install directory}/docs_{version}/mtb_user_guide.pdf).
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Connect the board to your PC using the provided USB cable through the KitProg3 USB connector.
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Use your favorite serial terminal application tool and connect to the KitProg3 COM port. Configure the terminal application to access the serial port using the following settings:
Baud rate: 115200 bps; Data: 8 bits; Parity: None; stop: 1 bit; Flow control: None; New line for receiving data: Line Feed(LF) or auto setting
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Program the board using one of the following:
Using Eclipse IDE for ModusToolbox™
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Select the application project in Project Explorer.
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In the Quick Panel, scroll down, and click <Application Name> Program (KitProg3_MiniProg4).
In other IDEs
Follow the instructions in your preferred IDE.
Using CLI
From the terminal, execute the
make programcommand to build and program the application using the default toolchain to the default target. The default toolchain is specified in the application's Makefile but you can override this value manually:make program TOOLCHAIN=<toolchain>Example:
make program TOOLCHAIN=GCC_ARM -
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After programming, the application starts automatically. Observe the messages on the UART terminal, and wait for the device to connect with the peer client (for example, the AIROC™ Bluetooth® Connect App). Use the KitProg3 COM port to view the Bluetooth® stack and application trace messages in the terminal window:
Figure 1. Log messages on KitProg3 COM port
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To test using the AIROC™ Bluetooth® Connect App, do the following (see the equivalent AIROC™ Bluetooth® Connect App screenshots in Figure 2 and Figure 3):
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Turn ON Bluetooth® on your Android or iOS device.
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Launch the AIROC™ Bluetooth® Connect App.
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Swipe down on the AIROC™ Bluetooth® Connect App home screen to start scanning for Bluetooth® LE peripherals; your device (“Hello") appears on the AIROC™ Bluetooth® Connect App home screen. Select your device to establish a Bluetooth® LE connection.
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In the Services page, choose the first characteristic to enable notifications/indications. Register for notifications or indications. This will, in turn, initiate the pairing process.
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Press the user button 1 in the kit and observe that notification/indication is being received in the mobile app.
Figure 2. Log messages on KitProg3 COM port
Figure 3. Testing with the AIROC™ Bluetooth® Connect App on Android
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You can choose the second characteristic, write a numeric value into it, and observe that the user LED on the board will blink as many times as the number written in the 'Blink' characteristic.Note that the numeric value written should range from 0-9 only. Figure 4. Log messages on KitProg3 COM port
-
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To forget a bonded device, press and hold the user button for more than 10 seconds and then release it. Ensure that the device is not in a connected state before performing this. User LED on the kit will be constantly turned ON for first 5 seconds and it will start blinking for 5 more seconds to indicate that the device is entering new mode.
Figure 5. Log messages on KitProg3 COM port
Note: This feature is available only for CYW920829M2EVK-02 and CYW989829M2EVB-01.
- Add airoc-hci-transport from library manager before enabling spy traces, check airoc-hci-transport README.md for more details. If airoc-hci-transport library is included in the application, it is recommended to initialize it (Call cybt_debug_uart_init()). If airoc-hci-transport library is present in the application, but you want to use retarget-io library to get application traces in Teraterm/putty, you need to set the ENABLE_AIROC_HCI_TRANSPORT_PRINTF MACRO value to 0 in the application. Otherwise printf messages of the application will not be visible.
#define ENABLE_AIROC_HCI_TRANSPORT_PRINTF 1
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Navigate to the application Makefile and open it. Find the Makefile variable
ENABLE_SPY_TRACESand set it to the value 1 as shown:ENABLE_SPY_TRACES = 1 -
Save the Makefile, and then build and program the application to the board.
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Open the ClientControl application and make the following settings:
- Set the baud rate to 3000000.
- Deselect the flow control checkbox.
- Select the serial port and click on an open port.
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Launch the BTSpy tool.
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Press and release the reset button on the board to get the BTSpy logs on the BTSpy tool.
You can debug the example to step through the code. In the IDE, use the <Application Name> Debug (KitProg3_MiniProg4) configuration in the Quick Panel. For more details, see the "Program and debug" section in the Eclipse IDE for ModusToolbox™ user guide.
Note: (Only while debugging PSoC™ 6 MCU) On the CM4 CPU, some code in main() may execute before the debugger halts at the beginning of main(). This means that some code executes twice - once before the debugger stops execution, and again after the debugger resets the program counter to the beginning of main(). See KBA231071 to learn about this and for the workaround.
Note: Debugging is of limited value when there is an active Bluetooth® LE connection because as soon as the Bluetooth® LE device stops responding, the connection will get dropped.
The code example configures the device as a Bluetooth® LE GAP Peripheral and GATT Server. The example implements a custom GATT service called 'Hello_Sensor' service and has two custom characteristics - Notify and Blink. The notify characteristic sends a notification or indication to the peer client device upon button press events. The Blink characteristic is used by the peer client to write the number of times the onboard user LED should blink.
The application uses a UART resource from the Hardware Abstraction Layer (HAL) to print debug messages on a UART terminal emulator. The UART resource initialization and retargeting of standard I/O to the UART port are done using the retarget-io library.
Upon reset, the application starts automatically and initializes BTSTACK and other device peripherals. The device starts to advertise its presence to the peer Central devices. Once a Bluetooth® LE connection is established, the peer client device can register for notifications/indications to be received using the CCCD handle of the Notify characteristic. Because the CCCD handle of the Notify characteristic requires write authentication, an attempt to enable notification/indication will trigger the pairing process at the Central side. Once the pairing process completes, the peer device's link keys and addresses are stored in the device's flash memory and therefore bonded.
The user button on the board is configured to trigger an interrupt on the falling edge. The user button has three functions based on the duration of button press. An onboard LED indicates the type of button press.
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Short button press: Press and release the button quickly to start undirected high advertisements if no connection exists. If a connection exists and notifications/indications are enabled, sends a notification/indication packet to the peer client device.
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Button press for 5 seconds: Press and hold the button for 5 seconds to enter pairing mode. In pairing mode, you can connect to a new peer device. An onboard LED turns ON for 5 seconds to indicate when to release the button to enter this mode.
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Button press for 10 seconds: Press and hold the button for 10 seconds to erase the bonding information from the flash memory of the device. The onboard LED will be constantly turned ON for first 5 seconds and it will start blinking for 5 more seconds to indicate that the device is entering new mode.
Note: The device must be disconnected from the peer client device before erasing the bonding information from the flash memory.
The peer client can also write the number of times the user LED on the board blinks using the Blink characteristic.
Figure 6. Hello Sensor process flowchart
This section explains the ModusToolbox™ resources and their configurations as used in this code example. Note that all the configurations explained in this section have already been implemented in the code example.
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Device Configurator: ModusToolbox™ stores the configuration settings of the application in the design.modus file. This file is used by the Device Configurator, which generates the configuration firmware. This firmware is stored in the application’s GeneratedSource folder.
By default, all applications in a workspace share the same design.modus file - i.e., they share the same pin configuration. Each BSP has a default design.modus file in the mtb_shared\TARGET_<bsp name><version>\COMPONENT_BSP_DESIGN_MODUS directory. It is not recommended to modify the configuration of a standard BSP directly.
To modify the configuration for a single application or to create a custom BSP, see the ModusToolbox™ user guide. This example uses the default configuration. See the Device Configurator guide.
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Bluetooth® Configurator: The Bluetooth® peripheral has an additional configurator called the “Bluetooth® Configurator” that is used to generate the Bluetooth® LE GATT database and various Bluetooth® settings for the application. These settings are stored in the file named design.cybt.
Note that unlike the Device Configurator, the Bluetooth® configurator settings and files are local to each respective application. The services and characteristics added are explained in the Design and implementation section. See the Bluetooth® Configurator guide.
Note: For PSoC™ 6 Bluetooth® LE-based BSPs (CY8CKIT-062-BLE, CY8CPROTO-063-BLE, CYBLE-416045-EVAL) with support for AIROC™ BTSTACK, if you want to use the bt-configurator tool, select the AIROC™ BTSTACK with Bluetooth® LE only (CYW20829, PSoC™ 6 with CYW43xxx Connectivity device) option from the drop-down to select the device. Do not use the PSoC™ Bluetooth® LE Legacy Stack (PSoC™ 6-BLE) option because it is not compatible with AIROC™ BTSTACK.
Table 1. Application resources
| Resource | Alias/object | Purpose |
|---|---|---|
| UART (HAL) | cy_retarget_io_uart_obj | UART HAL object used by Retarget-IO for Debug UART port |
| GPIO (HAL) | CYBSP_USER_LED1 | This LED will blink the number of times as written by the peer client device |
| GPIO (HAL) | CYBSP_USER_LED2 | This LED serves as an indication for a button press of 10-second duration |
| GPIO (HAL) | CYBSP_USER_BTN | Used to send notifications to the peer client on button press events |
| Resources | Links |
|---|---|
| Application notes | AN228571 – Getting started with PSoC™ 6 MCU on ModusToolbox™ AN215656 – PSoC™ 6 MCU: Dual-CPU system design |
| Code examples | Using ModusToolbox™ on GitHub |
| Device documentation | PSoC™ 6 MCU datasheets PSoC™ 6 technical reference manuals AIROC™ CYW20829 Bluetooth® LE SoC |
| Development kits | Select your kits from the Evaluation board finder page |
| Libraries on GitHub | mtb-pdl-cat1 – PSoC™ 6 Peripheral Driver Library (PDL) mtb-hal-cat1 – Hardware Abstraction Layer (HAL) library retarget-io – Utility library to retarget STDIO messages to a UART port |
| Middleware on GitHub | capsense – CAPSENSE™ library and documents psoc6-middleware – Links to all PSoC™ 6 MCU middleware |
| Tools | Eclipse IDE for ModusToolbox™ – ModusToolbox™ is a collection of easy-to-use software and tools enabling rapid development with Infineon MCUs, covering applications from embedded sense and control to wireless and cloud-connected systems using AIROC™ Wi-Fi and Bluetooth® connectivity devices. |
Infineon provides a wealth of data at www.infineon.com to help you select the right device, and quickly and effectively integrate it into your design.
For PSoC™ 6 MCU devices, see How to design with PSoC™ 6 MCU - KBA223067 in the Infineon Developer community.
Document title: CE235150 – Bluetooth® LE hello sensor
| Version | Description of change |
|---|---|
| 1.0.0 | New code example |
| 2.1.0 | Support for three PSoC™ 6 Bluetooth® LE BSPs Feature addition - long button press to remove bond data from NVRAM kv-store implementation using internal flash Workaround added in the application for Note 2 |
| 3.0.0 | Updated to support ModusToolbox™ v3.0 and BSPs v4.X |
| 3.1.0 | Introduction of pairing-mode, new button press mode to enter pairing-mode |
| 3.2.0 | Added support for CY8CEVAL-062S2-LAI-43439M2,CY8CPROTO-062S2-43439 |
| 3.3.0 | Removed CYW920829M2EVB-01 from supported kits Added support for CYW920829M2EVK-02 |
| 3.4.0 | Added support for CY8CEVAL-062S2-MUR-4373EM2 and CY8CEVAL-062S2-MUR-4373M2 |
| 3.5.0 | Fix reconnection issue due to duplication of bond data entries(BDA) in NVRAM |
| 3.6.0 | Added support for CYW989829M2EVB-01 |
| 3.7.0 | Added support for CY8CEVAL-062S2-CYW43022CUB and CY8CKIT-062S2-AI |
| 3.8.0 | Added support for CYW989829M2EVB-03 |
| 4.0.0 | BSP and BTStack-integration major update for BT Firmware as a separate asset and removal of combo devices as doesn't support fw as separate asset |
| 4.1.0 | Added support for CY8CEVAL-062S2-CYW955513SDM2WLIPA |
| 4.2.0 | Added support for KIT_XMC72_EVK_MUR_43439M2 |
All referenced product or service names and trademarks are the property of their respective owners.
The Bluetooth® word mark and logos are registered trademarks owned by Bluetooth SIG, Inc., and any use of such marks by Infineon is under license.
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