Multiple value in one characteristic

Question

Hello, 
 My project requires me to send acceleration data to phone. So, i have started with Custom BLE app. 
 Since i need to send 3 values, of x, y and z-axis. So i need to send multiple values to same characteristic. Can you guide me regarding this? 
 
 If any other approach serves me better, kindly do suggest me.

awneil · Answer

The definition of a "Characteristic", from the Bluetooth SIG website, is: 
 "Characteristics are defined attribute types that contain a single logical value." 
 https://www.bluetooth.com/specifications/gatt/characteristics/ 
 (my emphasis) 
 However, there's nothing to stop you having a 3-byte value - where the 1st byte represents X, the 2nd byte represents Y, and the 3rd byte represents Z 
 Or have a 6-byte value - where the 1st two bytes represent X, the 2nd two bytes represent Y, and the 3rd two bytes represent Z 
 etc, etc, ... 
 Or, as Karl Ylvisaker says, have a characteristic for X, and characteristic for Y, and a characteristic for Z. 
 See those tutorials. 
 
 EDIT 
 The Thingy:52 adopts the scheme of "packing" multiple values into a single Characteristic; eg, see the "Raw Data" Characteristic: 
 https://nordicsemiconductor.github.io/Nordic-Thingy52-FW/documentation/firmware_architecture.html#arch_motion

Multiple value in one characteristic

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