Bluetooth Classic and BLE GATT
Compare Bluetooth serial-style links with BLE services, characteristics, notifications and low-power behaviour.
Topology and objective
Phone central ↔ BLE peripheral service/characteristic; optional Classic SPP on supported boards.
Hardware and tools
- Supported development board
- USB data cable
- Current-limited supply
- Serial monitor and logic analyser when applicable
Security and RF safety
- Do not use fixed pairing PINs in production.nMinimise advertised personal/device data.nVerify board support before using Bluetooth Classic.
Practical procedure
- Advertise a unique lab device name.nScan and record RSSI.nConnect and discover services.nRead/write a test characteristic.nEnable notifications and measure update interval.
Telemetry / payload
{"characteristic":"temperature","value":24.6,"unit":"C"}Starter code / config
BLE service: 181A; custom characteristic: use a generated 128-bit UUID.Expected results
| Checkpoint | Expected | Tool |
|---|---|---|
| Discovery | Device and service UUID visible | BLE scannernNotification |
Troubleshooting
| Symptom | Check | Action |
|---|---|---|
| Cannot discover | Check advertising and permissions | Restart advertising with unique namenDisconnects |
Local-only sandbox
Commands & telemetry simulator
Send command
Simulator ready. No network connection is used.