This is the documentation for the latest (main) development branch. If you are looking for the documentation of previous releases, use the drop-down menu on the left and select the desired version.

central_hr

Overview

Similar to the central sample, This example demonstrates the functionality of scanning for and connecting to BLE heart rate monitor peripherals. Once connected successfully, it periodically sends heart rate information to the peripheral device.

Requirements

  • Board A with BLE support running this application

  • A BLE device around acting as a Heart-rate Peripheral or board B with BLE support running peripheral_hr application

Building and Running

Example Location：examples/bluetooth/central_hr

compile, burn, and more, see：Quick Start Guide

Running Result of Board A

  1. Successfully running will output the following logs

[I] (2) main: ver: 2.0.6dev build at Oct 17 2024 17:31:25
[I] (25) bt: LE SC enabled
[I] (147) bt: Identity: 28:6D:CD:68:D7:99 (public)
[I] (147) bt: HCI: version 4.2 (0x08) revision 0x0709, manufacturer 0x070c
[I] (147) bt: LMP: version 4.2 (0x08) subver 0x0709
[I] (147) central_hr: Bluetooth initialized
[I] (149) central_hr: Scanning successfully started
[I] (963) central_hr: [DEVICE]: 51:0C:84:0F:95:F2 (random), AD evt type 3, AD data len 31, RSSI -75
[I] (1022) central_hr: [DEVICE]: 61:CB:82:A1:3F:A0 (random), AD evt type 3, AD data len 31, RSSI -73

  1. Wait for development board B to be flashed with and run the firmware of the peripheral_hr example.

  2. After board A finds board B, it will connect、query service and subscribe the notification

[I] (1023) central_hr: [DEVICE]: 28:6D:CE:11:22:33 (public), AD evt type 0, AD data len 11, RSSI -34
[I] (2536) central_hr: Connected: 28:6D:CE:11:22:33 (public)
[I] (2628) central_hr: [ATTRIBUTE] handle 25
[I] (2728) central_hr: [ATTRIBUTE] handle 26
[I] (2829) central_hr: [ATTRIBUTE] handle 28
[I] (2829) central_hr: [SUBSCRIBED]

  1. After successfully subscribing, development board B starts sending heart rate information. Here is the log information from development board A

[I] (3731) central_hr: [NOTIFICATION] data 0x2000aefc length 2
[I] (4781) central_hr: [NOTIFICATION] data 0x2000aefc length 2
[I] (5731) central_hr: [NOTIFICATION] data 0x2000aefc length 2
[I] (6731) central_hr: [NOTIFICATION] data 0x2000aefc length 2
[I] (7731) central_hr: [NOTIFICATION] data 0x2000aefc length 2

Running result of board B

  1. Flash the firmware of the peripheral_hr example. Upon successful execution, the following log will be output:

[I] (6) main: ver: 2.0.6dev build at Oct 17 2024 17:31:48
[I] (28) bt: LE SC enabled
[I] (158) bt: Identity: 28:6D:CE:11:22:33 (public)
[I] (158) bt: HCI: version 4.2 (0x08) revision 0x0709, manufacturer 0x070c
[I] (159) bt: LMP: version 4.2 (0x08) subver 0x0709
[I] (159) peripheral_hr: Bluetooth initialized
[I] (161) peripheral_hr: Advertising successfully started

  1. Board B receives the connection request from board A will output the following logs

[I] (1251) peripheral_hr: Connected

  1. Development board B receives the subscription message from development board A and outputs the following log. It then periodically sends heart rate information to development board A.

[I] (1692) bt: HRS notifications enabled

Note

This example need to work together with periphal_hr example