User's Manual

Enhanced Class 1 Bluetooth v2.1 Module
User’s Guide
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162
CONN-GUIDE-BT740_v0.2
Attribute Tag
Data Type
Comments
MDC_ATTR_UNIT_CODE
2454
OID_TYPE
Var:Weight
Units
MDC_ATTR_TIME_PD_MSMT_ACT
IVE
2649
RELATIVE_TIME
Var:Time (int32)
MDC_ATTR_ATTRIBUTE_VAL_MA
P
2645
ATTR_VAL_MAP
2646,2448
MDC_ATTR_TIME_STAMP_ABS
2448
ABSOLUTE_TIME
Var:Time
MDC_ATTR_NU_VAL_OBS_BASIC
2636
BASIC_NU_OBS_VAL
Var:temperature
MDC_ATTR_NU_ACCUR_MSMT
2378
FLOAT_TYPE
Always: 1
MDC_ATTR_MSMT_STAT
2375
MEASUREMENT_STAT
US
Var:Meas. Stat.
The attributes commented as ‘variables’ expose to the host for reading and writing via the UART interface
using AT+HAG and AT+HAS commands respectively and are described in detail elsewhere in this
document.
The host identifies the variable attributes mentioned above on the UART interface using an attribute ID
and an additional sub ID. The concept of ‘sub ID’ is a Laird artefact and is not part of any IEEE standard,
but the attribute ID is the same as those defined in the IEEE standard in most cases. The complete list for
the Weigh Scale specialization is as per the table below and should be used with the agent attribute
read/write commands AT+HAG and AT+HAS.
Note: The attribute values passed back and forth from the host are NOT validated in any way by the
firmware in the Laird module. It is up to the host to ensure that the correct data writes into an
attribute. Any illegal values are picked up at time of Continua Alliance certification testing which
prevents certification.
Table 14-2: Variable Attributes in Thermometer Specialization
Attribute Name
(See IEEE spec for format)
Attr ID
Sub Id
Size in bytes
Temperature
2636
0
2
Temperature Units
2454
0
2
Absolute Time
2448
0
8
Power Status
2389
0
2
Battery Charge
2460
0
2
Time Battery Remain – value
2440
0
4
Time Battery Remain – unit
2440
1
2
Measurement Status
2375
0
2
System ID
2436
0
8
System Model – product name
2344
0
12
System Model – model name
2344
1
16