使用 CurieBLE 发送 20 字节的特征值

Question

Arduino/Genuino 101's CurieBLE library 的文档在“服务设计模式”部分中说明如下：

A characteristic value can be up to 20 bytes long. This is a key constraint in designing services. [...] You could also combine readings into a single characteristic, when a given sensor or actuator has multiple values associated with it.

[e.g. Accelerometer X, Y, Z => 200,133,150]

This is more efficient, but you need to be careful not to exceed the 20-byte limit. The accelerometer characteristic above, for example, takes 11 bytes as a ASCII-encoded string.

但是，API 中可用的类型 Characteristic constructors 仅限于以下内容：

BLEBoolCharacteristic

BLECharCharacteristic

BLEUnsignedCharCharacteristic

BLEShortCharacteristic

BLEUnsignedShortCharacteristic

BLEIntCharacteristic

BLEUnsignedIntCharacteristic

BLELongCharacteristic

BLEUnsignedLongCharacteristic

BLEFloatCharacteristic

BLEDoubleCharacteristic

None 这些类型的特征似乎能够容纳 20 字节的字符串。（我试过 BLECharCharacteristic，它似乎属于单个 char，而不是 char 数组。）

如何使用 CurieBLE，将字符串用作特征值，如文档中所述，这是一种有效的做法？

Answer 1

您的问题在 official arduino 101 example 中有所描述。几串代码如何设置数组：

BLECharacteristic heartRateChar("2A37",  // standard 16-bit characteristic UUID
    BLERead | BLENotify, 2);
...
const unsigned char heartRateCharArray[2] = { 0, (char)heartRate };
heartRateChar.setValue(heartRateCharArray, 2);

如您所见，使用 "setValue" 函数将所需数组作为参数来设置特征值。您可以将字符串作为指向数组的 char* 传递。

使用 CurieBLE 发送 20 字节的特征值

Sending 20-byte characteristic values with CurieBLE

arduino

intel

bluetooth-lowenergy