我将Polar H10用作心率监测器，我想使用Swift和Core蓝牙获得iOS的心率测量特性中的值。
以下是CBPeripheralDelegate的适当回调方法中的代码：
func peripheral(_ peripheral: CBPeripheral, didUpdateValueFor characteristic: CBCharacteristic, error: Error?) {
print("didUpdateValueFor")
if let error = error {
print("error:", error)
}
guard let value = characteristic.value else {
return
}
print("value:", value)
guard let stringValue = String(data: value, encoding: .utf8) else {
return
}
print("string value:", stringValue)
}
此Heart Rate Measurement的官方蓝牙网页显示了此未格式化的信息：
必填8位，注意：心率测量值字段的格式取决于标志字段的位0。 C1 uint8 org.bluetooth.unit.period.beats_per_minute注意：心率测量值字段的格式取决于“标志”字段的位0。 C2 uint16 org.bluetooth.unit.period.beats_per_minute能源消耗字段的存在取决于“标志”字段的第3位。 C3 uint16 org.bluetooth.unit.energy.joule C4 uint16 org.bluetooth.unit.time.second分辨率为1/1024秒上表中的字段按从LSO到MSO的顺序排列。 LSO =最低有效八位位组，MSO =最高有效八位位组。
我不知道文档的含义。特别是我不明白C1，C2，C3和C4是指什么。
character.value是数据类型。我该如何处理该数据对象？如何获得所需的价值？我首先要获得RR值。
[类似的帖子，但是它们对我没有帮助，因为他们使用不同的工具和语言，或者没有很好的答案。
更新：
我自从发现Heart Rate Measurement的页面是一个xml文件。使用可以显示该文件的应用程序打开该文件后，我可以从该文件中获取所需的信息。我第一次看到它是在Safari中。它不能很好地显示xml文件。这是文件：
<?xml version="1.0" encoding="UTF-8"?>
<!-- Copyright 2011 Bluetooth SIG, Inc. All rights reserved. -->
<Characteristic xsi:noNamespaceSchemaLocation="http://schemas.bluetooth.org/Documents/characteristic.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" type="org.bluetooth.characteristic.heart_rate_measurement" uuid="2A37" name="Heart Rate Measurement">
<InformativeText>
</InformativeText>
<Value>
<Field name="Flags">
<Requirement>Mandatory</Requirement>
<Format>8bit</Format>
<BitField>
<Bit index="0" size="1" name="Heart Rate Value Format bit">
<Enumerations>
<Enumeration key="0" value="Heart Rate Value Format is set to UINT8. Units: beats per minute (bpm)" requires="C1" />
<Enumeration key="1" value="Heart Rate Value Format is set to UINT16. Units: beats per minute (bpm)" requires="C2" />
</Enumerations>
</Bit>
<Bit index="1" size="2" name="Sensor Contact Status bits">
<Enumerations>
<Enumeration key="0" value="Sensor Contact feature is not supported in the current connection" />
<Enumeration key="1" value="Sensor Contact feature is not supported in the current connection" />
<Enumeration key="2" value="Sensor Contact feature is supported, but contact is not detected" />
<Enumeration key="3" value="Sensor Contact feature is supported and contact is detected" />
</Enumerations>
</Bit>
<Bit index="3" size="1" name="Energy Expended Status bit">
<Enumerations>
<Enumeration key="0" value="Energy Expended field is not present" />
<Enumeration key="1" value="Energy Expended field is present. Units: kilo Joules" requires="C3"/>
</Enumerations>
</Bit>
<Bit index="4" size="1" name="RR-Interval bit">
<Enumerations>
<Enumeration key="0" value="RR-Interval values are not present." />
<Enumeration key="1" value="One or more RR-Interval values are present." requires="C4"/>
</Enumerations>
</Bit>
<ReservedForFutureUse index="5" size="3"></ReservedForFutureUse>
</BitField>
</Field>
<Field name="Heart Rate Measurement Value (uint8)">
<InformativeText>
Note: The format of the Heart Rate Measurement Value field is dependent upon bit 0 of the Flags field.
</InformativeText>
<Requirement>C1</Requirement>
<Format>uint8</Format>
<Unit>org.bluetooth.unit.period.beats_per_minute</Unit>
</Field>
<Field name="Heart Rate Measurement Value (uint16)">
<InformativeText>
Note: The format of the Heart Rate Measurement Value field is dependent upon bit 0 of the Flags field.
</InformativeText>
<Requirement>C2</Requirement>
<Format>uint16</Format>
<Unit>org.bluetooth.unit.period.beats_per_minute</Unit>
</Field>
<Field name="Energy Expended">
<InformativeText>The presence of the Energy Expended field is dependent upon bit 3 of the Flags field.</InformativeText>
<Requirement>C3</Requirement>
<Format>uint16</Format>
<Unit>org.bluetooth.unit.energy.joule</Unit>
</Field>
<Field name="RR-Interval">
<InformativeText>
<!-- The presence of the RR-Interval field is dependent upon bit 4 of the Flags field.
<p>The RR-Interval value represents the time between two R-Wave detections.</p>
<p>Because several RR-Intervals may be measured between transmissions of the HEART RATE MEASUREMENT characteristic,
multiple RR-Interval sub-fields may be present in the characteristic. The number of RR-Interval sub-fields present
is determined by a combination of the overall length of the characteristic and whether or not the characteristic contains
the Energy Expended field.</p>
<p>Where there are multiple RR-Interval values transmitted in the HEART RATE MEASUREMENT characteristic, the field uses the following format:</p>
<p>RR-Interval Value 0 (LSO...MSO), RR-Interval Value 1 (LSO...MSO), RR-Interval Value 2 (LSO...MSO), RR-Interval Value n (LSO...MSO).</p>
<p>Where the RR-Interval Value 0 is older than the RR-Interval Value 1.</p>
<p>RR-Interval Value 0 is transmitted first followed by the newer measurements.</p>-->
</InformativeText>
<Requirement>C4</Requirement>
<Format>uint16</Format>
<Unit>org.bluetooth.unit.time.second</Unit>
<Description>Resolution of 1/1024 second</Description>
</Field>
</Value>
<Note> <p>The fields in the above table are in the order of LSO to MSO. Where LSO = Least Significant Octet and MSO = Most Significant Octet.</p>
</Note>
</Characteristic>
首先，您需要将特征值数据转换为UInt8数组，然后需要检查您的心率传感器是否在该索引处提供值。我在我的项目中使用以下代码，并且工作正常。希望它也会对您有帮助。