Bluetooth GATT Characteristic Reference
Protocol Mode (0x2A4E)
The Protocol Mode characteristic is used to expose the current protocol mode of the HID Service with which it is associated, or to set the desired protocol mode of the HID Service.
Quick Summary
Payload length is 1 bytes. This page is generated from official GATT XML and presented as implementation-ready guidance.
At a Glance
Key reference details for BLE implementation, interoperability testing, and AI-assisted troubleshooting.
| Property | Value |
|---|---|
| Name | Protocol Mode |
| UUID | 0x2A4E |
| Type | org.bluetooth.characteristic.protocol_mode |
| XML Root | Characteristic |
| Source File | org.bluetooth.characteristic.protocol_mode.xml |
| Field Count | 1 |
Field Specification
Parsed field definitions from the source XML value structure.
| Field | Requirement | Format | Unit | Exponent | Notes |
|---|---|---|---|---|---|
| Protocol Mode Value | Mandatory | uint8 | - | - | - |
Byte Layout and Decode
Payload length is 1 bytes.
function decodePayload(dataView, offset = 0) {
const protocol_mode_value = dataView.getUint8(offset + 0);
return { protocol_mode_value };
}Use Cases and Integration Notes
BLE Telemetry
Map characteristic values into dashboards and alerts for device observability.
Firmware Regression
Compare decoded fields across builds to detect protocol or scaling changes.
App Integration
Build stable parsing paths that convert raw payloads into typed app models.
Implementation Checklist
- Validate payload length and mandatory fields before decode.
- Decode with Bluetooth-specified signedness, unit, and exponent handling.
- Convert units at presentation boundaries to avoid drift in business logic.
- Persist raw packets and decoded values for reproducible troubleshooting.
FAQ
What is Protocol Mode in Bluetooth GATT?
Protocol Mode is defined as a Bluetooth GATT characteristic entry with type org.bluetooth.characteristic.protocol_mode and UUID 0x2A4E.
What UUID identifies Protocol Mode?
The UUID for Protocol Mode is 0x2A4E.
How should I parse Protocol Mode?
Payload length is 1 bytes.
Where does this definition come from?
This page is generated from the Bluetooth SIG mirror XML in the oesmith/gatt-xml repository.
How does this page support BLE implementation?
The page combines structured tables, practical Q&A, and JSON-LD metadata to help teams validate integrations and troubleshoot consistently.