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Bluetooth GATT Characteristic Reference

Service Changed (0x2A05)

org.bluetooth.characteristic.gatt.service_changed

Service Changed is defined in the Bluetooth GATT XML specification with type org.bluetooth.characteristic.gatt.service_changed and UUID 0x2A05.

Quick Summary

Payload length is 4 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.

PropertyValue
NameService Changed
UUID0x2A05
Typeorg.bluetooth.characteristic.gatt.service_changed
XML RootCharacteristic
Source Fileorg.bluetooth.characteristic.gatt.service_changed.xml
Field Count2

Field Specification

Parsed field definitions from the source XML value structure.

Field Requirement Format Unit Exponent Notes
Start of Affected Attribute Handle RangeMandatoryuint16---
End of Affected Attribute Handle RangeMandatoryuint16---

Byte Layout and Decode

Payload length is 4 bytes.

function decodePayload(dataView, offset = 0) {
  const start_of_affected_attribute_handle_range = dataView.getUint16(offset + 0, true);
  const end_of_affected_attribute_handle_range = dataView.getUint16(offset + 2, true);
  return { start_of_affected_attribute_handle_range, end_of_affected_attribute_handle_range };
}

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 Service Changed in Bluetooth GATT?

Service Changed is defined as a Bluetooth GATT characteristic entry with type org.bluetooth.characteristic.gatt.service_changed and UUID 0x2A05.

What UUID identifies Service Changed?

The UUID for Service Changed is 0x2A05.

How should I parse Service Changed?

Payload length is 4 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.