Android BLE - how to detect a heart rate sensor

Question

1. Im trying to connect to an external heart rate sensor using BLE. As Im getting 5 different characteristic values, how to detect what values is used for heart rate monitoring?

2. How to convert byte array to readable result?

Answer 1

1. The standardised Heart Rate service is 0x180D and the characteristic is 0x2A37, so you need to read data off this.
2. The heart rate value is usually exposed over 1 byte only (because values 0-255 covers the range of heart rate values in beat per minute (bpm). If you want to read other values exposed by the device then the document that Michael Kotzjan shared is useful in deducting what the byte array values mean.

More useful references:-

• How to use Android BLE to communicate with Bluetooth Devices (HRM)
• The ultimate guide to Android BLE
• Making Android BLE work