The Characteristic class¶
A Bluetooth LE “characteristic” represents a short data item which can be read or written. These can be fixed (e.g. a string representing the manufacturer name) or change dynamically (such as the current temperature or state of a button). Most interaction with Bluetooth LE peripherals is done by reading or writing characteristics.
Constructor¶
You should not construct Characteristic objects directly. Instead, use the
getCharacteristics() method of a connected Peripheral object.
Instance Methods¶
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read()¶ Reads the current value of a characteristic as a string of bytes. For Python 2.x this is a value of type str, and on Python 3.x this is of type bytes. This may be used with the struct module to extract integer values from the data.
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write(data[, withResponse=False])¶ Writes the given data to the characteristic. data should be of type str for Python 2.x, and type bytes for Python 3.x. Bluetooth LE allows the sender to request the peripheral to send a response to confirm that the data has been received. Setting the withResponse parameter to True will make this request. A BTLEException will be raised if the confirmation process fails.
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supportsRead()¶ Returns True if the characteristic can be read (as indicated by its properties) and False otherwise.
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propertiesToString()¶ Returns a string describing the characteristic properties (‘READ’, ‘WRITE’, etc).
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getHandle()¶ Returns the 16-bit integer value used to identify the characteristic in the underlying GATT protocol. This may be useful to distinguish between notifications from different characteristics (see Working with notifications for further information).