我正在使用 Polar H10 作为心率监测器，我想使用 Swift 和 Core Bluetooth 获取 iOS 中心率测量特性中的值。
以下是 CBPeripheralDelegate 的相应回调方法中的代码:
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)
}
官方蓝牙网页Heart Rate Measurement显示此未格式化的信息:
Mandatory 8bit Note: The format of the Heart Rate Measurement Value field is dependent upon bit 0 of the Flags field. C1 uint8 org.bluetooth.unit.period.beats_per_minute Note: The format of the Heart Rate Measurement Value field is dependent upon bit 0 of the Flags field. C2 uint16 org.bluetooth.unit.period.beats_per_minute The presence of the Energy Expended field is dependent upon bit 3 of the Flags field. C3 uint16 org.bluetooth.unit.energy.joule C4 uint16 org.bluetooth.unit.time.second Resolution of 1/1024 second The fields in the above table are in the order of LSO to MSO. Where LSO = Least Significant Octet and MSO = Most Significant Octet.
我无法弄清楚文档的含义。特别是我不明白 C1、C2、C3 和 C4 指的是什么。
特征值是数据类型。我该如何处理该 Data 对象？如何获得我需要的值？我首先想要 RR 值。
有类似的帖子，但它们对我没有帮助，因为他们使用不同的工具和不同的语言，或者他们没有很好的答案。
更新:
我后来发现 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，我能够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>
最佳答案
这是我获得 RR 间隔的工作解决方案:
guard let characteristicData = characteristic.value else { return nil }
let byteArray = [UInt8](characteristicData)
var rawRRinterval = 0
//if fifth bit (index 4) is set -> RR-Inteval present (00010000 = 16)
if (byteArray[0] & 16) != 0{
print("One or more RR-Interval values are present.")
//00000000 (0) = heart rate 8 bit in [1]
//00000001 (1) = heart rate 16 bit in [1] + [2]
//00000110 () = sensor contact flags - status decoded in flags no other field needed
//00001000 (8) = energy status 16 bit in [2] + [3]
//00001001 (9) = energy status 16 bit in [3] + [4]
//00010000 (16) = RR-value 16 bit in [2] + [3]
//00010010 (18) = RR-value 16 bit in [2] + [3]
//00010100 (20) = RR-value 16 bit in [2] + [3]
//00010110 (22) = RR-value 16 bit in [2] + [3]
//00010001 (17) = RR-value 16 bit in [3] + [4]
//00010011 (19) = RR-value 16 bit in [3] + [4]
//00010101 (21) = RR-value 16 bit in [3] + [4]
//00010111 (23) = RR-value 16 bit in [3] + [4]
//00011000 (24) = RR-value 16 bit in [4] + [5]
//00011010 (26) = RR-value 16 bit in [4] + [5]
//00011100 (28) = RR-value 16 bit in [4] + [5]
//00011110 (30) = RR-value 16 bit in [4] + [5]
//00011001 (25) = RR-value 16 bit in [5] + [6]
//00011011 (27) = RR-value 16 bit in [5] + [6]
//00011101 (29) = RR-value 16 bit in [5] + [6]
//00011111 (31) = RR-value 16 bit in [5] + [6]
switch byteArray[0] {
case 16,18,20,22:
//rr-value in [2] und [3]
rawRRinterval = Int(byteArray[2]) + (Int(byteArray[3]) << 8)
case 17,19,21,23:
//rr-value in [3] und [4]
rawRRinterval = Int(byteArray[3]) + (Int(byteArray[4]) << 8)
case 24,26,28,30:
//rr-value in [4] und [5]
rawRRinterval = Int(byteArray[4]) + (Int(byteArray[5]) << 8)
case 25,27,29,31:
//rr-value in [5] und [6]
rawRRinterval = Int(byteArray[4]) + (Int(byteArray[5]) << 8)
}else{
print("RR-Interval values are not present.")
}
//Resolution of 1/1024 second
let rrInSeconds: Double = Double(rawRRinterval)/1024
print("💢 rrInSeconds: \(rrInSeconds)")
let rrInMilSeconds: Double = Double(rrInSeconds) * 1000
print("💢 rrInMilSeconds: \(rrInMilSeconds)")
let value = (Double(rawRRinterval) / 1024.0 ) * 1000.0
print("💢 value: \(value)")
return rrInMilSeconds
关于ios - 如何在 iOS 中使用 Swift 和 Core 蓝牙从 Polar H10 获取心率测量值？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/60348615/