src.bluetooth_sig.gatt.characteristics.cgm_measurement¶

CGM Measurement characteristic implementation.

Implements the CGM Measurement characteristic (0x2AA7). The characteristic value contains one or more CGM Measurement Records concatenated together.

Each record contains:: Size (uint8) – total size of the record including this field Flags (uint8) – controls presence of optional fields CGM Glucose Concentration (medfloat16) Time Offset (uint16) – minutes since session start Sensor Status Annunciation (0-3 octets, flag-gated) CGM Trend Information (medfloat16, optional) CGM Quality (medfloat16, optional)
Flag-bit assignments:: Bit 0: CGM Trend Information present Bit 1: CGM Quality present Bits 2-4: Reserved Bit 5: Warning-Octet present (Sensor Status Annunciation) Bit 6: Cal/Temp-Octet present (Sensor Status Annunciation) Bit 7: Status-Octet present (Sensor Status Annunciation)

References

Bluetooth SIG Continuous Glucose Monitoring Service org.bluetooth.characteristic.cgm_measurement (GSS YAML)

Classes¶

Name	Description
`CGMCalTempOctet`	CGM Sensor Status Annunciation — Cal/Temp octet (bits 8-15).
`CGMMeasurementCharacteristic`	CGM Measurement characteristic (0x2AA7).
`CGMMeasurementData`	Parsed data from CGM Measurement characteristic.
`CGMMeasurementFlags`	CGM Measurement record flags.
`CGMMeasurementRecord`	A single CGM Measurement Record.
`CGMSensorStatusOctet`	CGM Sensor Status Annunciation — Status octet (bits 0-7).
`CGMWarningOctet`	CGM Sensor Status Annunciation — Warning octet (bits 16-23).

Module Contents¶

class src.bluetooth_sig.gatt.characteristics.cgm_measurement.CGMCalTempOctet¶

Bases: enum.IntFlag

CGM Sensor Status Annunciation — Cal/Temp octet (bits 8-15).

CALIBRATION_NOT_ALLOWED = 2¶

CALIBRATION_PENDING = 64¶

CALIBRATION_RECOMMENDED = 4¶

CALIBRATION_REQUIRED = 8¶

SENSOR_TEMP_TOO_HIGH = 16¶

SENSOR_TEMP_TOO_LOW = 32¶

TIME_SYNC_REQUIRED = 1¶

class src.bluetooth_sig.gatt.characteristics.cgm_measurement.CGMMeasurementCharacteristic(info: src.bluetooth_sig.types.CharacteristicInfo | None = None, validation: src.bluetooth_sig.gatt.characteristics.characteristic_meta.ValidationConfig | None = None)¶

Bases: src.bluetooth_sig.gatt.characteristics.base.BaseCharacteristic[CGMMeasurementData]

CGM Measurement characteristic (0x2AA7).

Contains one or more CGM Measurement Records concatenated together. Each record is self-sized via its leading Size byte.

allow_variable_length: bool = True¶

expected_type¶

min_length: int = 6¶

class src.bluetooth_sig.gatt.characteristics.cgm_measurement.CGMMeasurementData¶

Bases: msgspec.Struct

Parsed data from CGM Measurement characteristic.

records¶: List of CGM Measurement Records.

records: tuple[CGMMeasurementRecord, Ellipsis]¶

class src.bluetooth_sig.gatt.characteristics.cgm_measurement.CGMMeasurementFlags¶

Bases: enum.IntFlag

CGM Measurement record flags.

CAL_TEMP_OCTET_PRESENT = 64¶

QUALITY_PRESENT = 2¶

STATUS_OCTET_PRESENT = 128¶

TREND_INFORMATION_PRESENT = 1¶

WARNING_OCTET_PRESENT = 32¶

class src.bluetooth_sig.gatt.characteristics.cgm_measurement.CGMMeasurementRecord¶

Bases: msgspec.Struct

A single CGM Measurement Record.

size¶: Total size of this record in bytes (including the size field).

flags¶: Raw 8-bit flags field.

glucose_concentration¶: Glucose concentration in mg/dL.

time_offset¶: Minutes since session start.

status_octet¶: Sensor status octet (8 bits). None if absent.

cal_temp_octet¶: Calibration/temperature octet (8 bits). None if absent.

warning_octet¶: Warning octet (8 bits). None if absent.

trend_information¶: Glucose trend rate (mg/dL/min). None if absent.

quality¶: CGM quality percentage. None if absent.

cal_temp_octet: CGMCalTempOctet | None = None¶

flags: CGMMeasurementFlags¶

glucose_concentration: float¶

quality: float | None = None¶

size: int¶

status_octet: CGMSensorStatusOctet | None = None¶

time_offset: int¶

trend_information: float | None = None¶

warning_octet: CGMWarningOctet | None = None¶

class src.bluetooth_sig.gatt.characteristics.cgm_measurement.CGMSensorStatusOctet¶

Bases: enum.IntFlag

CGM Sensor Status Annunciation — Status octet (bits 0-7).

DEVICE_BATTERY_LOW = 2¶

DEVICE_SPECIFIC_ALERT = 16¶

GENERAL_DEVICE_FAULT = 32¶

SENSOR_MALFUNCTION = 8¶

SENSOR_TYPE_INCORRECT = 4¶

SESSION_STOPPED = 1¶

class src.bluetooth_sig.gatt.characteristics.cgm_measurement.CGMWarningOctet¶

Bases: enum.IntFlag

CGM Sensor Status Annunciation — Warning octet (bits 16-23).

RATE_OF_DECREASE_EXCEEDED = 16¶

RATE_OF_INCREASE_EXCEEDED = 32¶

RESULT_HIGHER_THAN_DEVICE_CAN_PROCESS = 128¶

RESULT_HIGHER_THAN_HYPER = 8¶

RESULT_HIGHER_THAN_PATIENT_HIGH = 2¶

RESULT_LOWER_THAN_DEVICE_CAN_PROCESS = 64¶

RESULT_LOWER_THAN_HYPO = 4¶

RESULT_LOWER_THAN_PATIENT_LOW = 1¶