STM32WBA Bluetooth® LE – Data Throughput Measurement

4. STM32WBA Data Throughput Server example description

4.1. Project directory

The "BLE_DataThroughput_Server" application is available by downloading STM32CubeWBA MCU Package.

Data Throughput Server project directory
File:DT server directory 1.png

4.2. Project description

4.2.1. Structure

Software project structure with the most important parts:

Data Throughput Server project structure
File:DT server structure from ppt 1.png

4.2.2. Application initialization

The different steps of the application initialization are described below:

4.2.3. GAP and GATT initialization and interaction

The Bluetooth LE Data Throughput Server application initialization is done within app_ble.c

• Start the BLE stack - initialize the device as peripheral - configure and start advertising: ADV parameters, local name, UUID - APP_BLE_init()
• Call the services controller initialization SVCCTL_Init() - svc_ctl.c
• Manage the GAP event - SVCCTL_App_Notification()
  • EVT_LE_CONN_COMPLETE - provides information of the connection interval, slave latency, supervision timeout
  • EVT_LE_CONN_UPDATE_COMPLETE - provides the new information of the connection
  • EVT_DISCONN_COMPLETE - informs the application about the link disconnection and the reason
  • EVT_ENCRYPT_CHANGE - informs the application weather the link is encrypted

The Services management is done by the service controller - svc_ctl.c

• Call the Initialization function of all the developed services - SVCCTL_SvcInit()
  • Data Throughput Service - DT_SERV_Init() - dt_serv.c
• Register Services Event Handler - SVCCTL_RegisterSvcHandler(...)
• Manage events - SVCCTL_UserEvtRx ()- from the BLE Host Stack and redirect them to the services registered - DT_SERV_EventHandler() - or gap event handler - SVCCTL_App_Notification

The Data Throughput Service dt_serv.c manages the specification of the service:

• Service Init - DT_SERV_Init()
  • Register Data Throughput Event Handle to Service Controller - SVCCTL_RegisterSvcHandler(DT_SERV_EventHandler);
  • Initialize Service UUID – add Data Throughput service as Primary services

TBU

• • • Initialize Heart rate measurement characteristic
    • Initialize Body Sensor location characteristic
• Update Heart Rate measurement characteristic - HRS_UpdateChar()
• Update Body Sensor location characteristic Value - HRS_UpdateChar()
• Manage the GATT event from BLE Stack - DT_SERV_EventHandler()
  • ACI_GATT_WRITE_PERMIT_REQ_VSEVT_CODE
    • Reception of a Write Command: HR Control Point Characterictic Value
      • Send an aci_gatt_write_response() with an OK or KO status.
      • Notify the application to Reset Energy Expended - HRS_Notification(HRS_RESET_ENERGY_EXPENDED_EVT)
  • ACI_GATT_ATTRIBUTE_MODIFIED_VSEVT_CODE
    • Reception of an attribute modification - HR Measurement Characteristics Description Value : ENABLE or DISABLE Notification
      • Notify application of the Measurement Notification - HRS_Notification(HRS_NOTIFICATION_ENABLED/DISABLED)

Heart Rate Sensor software module interaction

The application level of the Heart Rate Sensor is done with hrs_app.c:

• Initialization of the context of the application
  • Measurement value flags support
  • Body sensor location - HRS_BODY_SENSOR_LOCATION_HAND
• Receive notification from the Heart Rate Service - HRS_Notification()
• When Heart rate measurement characteristics are enabled by the remote, simulate every 1 s the Heart Rate Measure (HRSAPP_Measurement) and increase the energy expended to transfer to the remote device (collector) - HRS_UpdateChar()

5. STM32WBA Data Throughput Client example description

5.1. Project directory

The "BLE_DataThroughput_Client" application is available by downloading STM32CubeWBA MCU Package.

Data Throughput Client project directory
File:DT client directory 1.png

5.2. Project description

5.2.1. Structure

Software project structure with the most important parts:

Data Throughput Client project structure
File:DT client structure from ppt.png

5.2.2. Application initialization

The different steps of the application initialization are described below: