Bluetooth GATT Characteristic Reference
Current Time (0x2A2B)
Current Time is defined in the Bluetooth GATT XML specification with type org.bluetooth.characteristic.current_time and UUID 0x2A2B.
Quick Summary
Payload length is profile-defined or variable based on field formats. 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 | Current Time |
| UUID | 0x2A2B |
| Type | org.bluetooth.characteristic.current_time |
| XML Root | Characteristic |
| Source File | org.bluetooth.characteristic.current_time.xml |
| Field Count | 2 |
Field Specification
Parsed field definitions from the source XML value structure.
| Field | Requirement | Format | Unit | Exponent | Notes |
|---|---|---|---|---|---|
| Exact Time 256 | Mandatory | N/A | - | - | - |
| Adjust Reason | Mandatory | 8bit | - | - | - |
Bit Map
Bit-level enumerations extracted from the XML BitField definition.
| Field | Bit | Size | Name | 0 Means | 1 Means |
|---|---|---|---|---|---|
| Adjust Reason | 0 | 1 | Bit | No manual time update | Manual time update |
| Adjust Reason | 1 | 1 | Bit | No external reference time update | External reference time update |
| Adjust Reason | 2 | 1 | Bit | No change of time zone | Change of time zone |
| Adjust Reason | 3 | 1 | Bit | No change of DST (daylight savings time) | Change of DST (daylight savings time) |
Byte Layout and Decode
Payload length is profile-defined or variable based on field formats.
function decodePayload(dataView, offset = 0) {
// Parse exact_time_256 (N/A) according to Bluetooth format rules.
// Parse adjust_reason (8bit) according to Bluetooth format rules.
return { exact_time_256, adjust_reason };
}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 Current Time in Bluetooth GATT?
Current Time is defined as a Bluetooth GATT characteristic entry with type org.bluetooth.characteristic.current_time and UUID 0x2A2B.
What UUID identifies Current Time?
The UUID for Current Time is 0x2A2B.
How should I parse Current Time?
Payload length is profile-defined or variable based on field formats.
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.