Luca Mottola / Mbed OS IOTAtelier1819-BLELed

BLE example of a write characteristic to control a Led

readme.md@0:c6a8f2b3efb6, 2016-07-26 (annotated)

Committer:
Vincent Coubard
Date:
Tue Jul 26 14:47:19 2016 +0100
Revision:
0:c6a8f2b3efb6
Child:
2:864ddfb70a9c
Update example at tag mbed-os-5.0.1-rc1

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Vincent Coubard 0:c6a8f2b3efb6 1 To help you create your own BLE services, we have created this service template.
Vincent Coubard 0:c6a8f2b3efb6 2 The LED example demonstrates the use of a read-write characteristic to control a
Vincent Coubard 0:c6a8f2b3efb6 3 LED through a phone app.
Vincent Coubard 0:c6a8f2b3efb6 4
Vincent Coubard 0:c6a8f2b3efb6 5 The template covers:
Vincent Coubard 0:c6a8f2b3efb6 6
Vincent Coubard 0:c6a8f2b3efb6 7 * Setting up advertising and connection states.
Vincent Coubard 0:c6a8f2b3efb6 8 * Assigning UUIDs to the service and its characteristic.
Vincent Coubard 0:c6a8f2b3efb6 9 * Creating an input characteristic: read-write, boolean. This characteristic offers control of the LED.
Vincent Coubard 0:c6a8f2b3efb6 10 * Constructing a service class and adding it to the BLE stack.
Vincent Coubard 0:c6a8f2b3efb6 11
Vincent Coubard 0:c6a8f2b3efb6 12 # Running the application
Vincent Coubard 0:c6a8f2b3efb6 13
Vincent Coubard 0:c6a8f2b3efb6 14 ## Requirements
Vincent Coubard 0:c6a8f2b3efb6 15
Vincent Coubard 0:c6a8f2b3efb6 16 The sample application can be seen on any BLE scanner on a smartphone. If you don't have a scanner on your phone, please install :
Vincent Coubard 0:c6a8f2b3efb6 17
Vincent Coubard 0:c6a8f2b3efb6 18 - [nRF Master Control Panel](https://play.google.com/store/apps/details?id=no.nordicsemi.android.mcp) for Android.
Vincent Coubard 0:c6a8f2b3efb6 19
Vincent Coubard 0:c6a8f2b3efb6 20 - [LightBlue](https://itunes.apple.com/gb/app/lightblue-bluetooth-low-energy/id557428110?mt=8) for iPhone.
Vincent Coubard 0:c6a8f2b3efb6 21
Vincent Coubard 0:c6a8f2b3efb6 22 Hardware requirements are in the [main readme](https://github.com/ARMmbed/mbed-os-example-ble/blob/master/README.md).
Vincent Coubard 0:c6a8f2b3efb6 23
Vincent Coubard 0:c6a8f2b3efb6 24 *NOTE:* If you have more than a single mbed board (e.g. nrf51dk or mkit) you can
Vincent Coubard 0:c6a8f2b3efb6 25 run the BLE_LED and BLE_LEDBlinker at the same time. For more information please
Vincent Coubard 0:c6a8f2b3efb6 26 refer to the BLE_LEDBlinker demo.
Vincent Coubard 0:c6a8f2b3efb6 27
Vincent Coubard 0:c6a8f2b3efb6 28 ## Building instructions
Vincent Coubard 0:c6a8f2b3efb6 29
Vincent Coubard 0:c6a8f2b3efb6 30 Building instructions for all samples are in the [main readme](https://github.com/ARMmbed/mbed-os-example-ble/blob/master/README.md).
Vincent Coubard 0:c6a8f2b3efb6 31
Vincent Coubard 0:c6a8f2b3efb6 32 ## Checking for success
Vincent Coubard 0:c6a8f2b3efb6 33
Vincent Coubard 0:c6a8f2b3efb6 34 **Note:** Screens captures depicted below show what is expected from this example if the scanner used is *nRF Master Control Panel* version 4.0.5. If you encounter any difficulties consider trying another scanner or another version of nRF Master Control Panel. Alternative scanners may require reference to their manuals.
Vincent Coubard 0:c6a8f2b3efb6 35
Vincent Coubard 0:c6a8f2b3efb6 36
Vincent Coubard 0:c6a8f2b3efb6 37 1. Build the application and install it on your board as explained in the building instructions.
Vincent Coubard 0:c6a8f2b3efb6 38 1. Open the BLE scanner on your phone.
Vincent Coubard 0:c6a8f2b3efb6 39
Vincent Coubard 0:c6a8f2b3efb6 40 1. Start a scan.
Vincent Coubard 0:c6a8f2b3efb6 41
Vincent Coubard 0:c6a8f2b3efb6 42 ![](img/start_scan.png)
Vincent Coubard 0:c6a8f2b3efb6 43
Vincent Coubard 0:c6a8f2b3efb6 44 **figure 1** How to start scan using nRF Master Control Panel 4.0.5
Vincent Coubard 0:c6a8f2b3efb6 45
Vincent Coubard 0:c6a8f2b3efb6 46 1. Find your device; it should be named `LED`.
Vincent Coubard 0:c6a8f2b3efb6 47
Vincent Coubard 0:c6a8f2b3efb6 48 ![](img/scan_results.png)
Vincent Coubard 0:c6a8f2b3efb6 49
Vincent Coubard 0:c6a8f2b3efb6 50 **figure 2** Scan results using nRF Master Control Panel 4.0.5
Vincent Coubard 0:c6a8f2b3efb6 51
Vincent Coubard 0:c6a8f2b3efb6 52 1. Establish a connection with your device.
Vincent Coubard 0:c6a8f2b3efb6 53
Vincent Coubard 0:c6a8f2b3efb6 54 ![](img/connection.png)
Vincent Coubard 0:c6a8f2b3efb6 55
Vincent Coubard 0:c6a8f2b3efb6 56 **figure 3** How to establish a connection using Master Control Panel 4.0.5
Vincent Coubard 0:c6a8f2b3efb6 57
Vincent Coubard 0:c6a8f2b3efb6 58 1. Discover the services and the characteristics on the device. The *LED service* has the UUID `0xA000` and includes the *LED state characteristic* which has the UUID `0xA001`. Depending on your scanner, non standard 16-bit UUID's can be displayed as 128-bit UUID's. If it is the case the following format will be used: `0000XXXX-0000-1000-8000-00805F9B34FB` where `XXXX` is the hexadecimal representation of the 16-bit UUID value.
Vincent Coubard 0:c6a8f2b3efb6 59
Vincent Coubard 0:c6a8f2b3efb6 60 ![](img/discovery.png)
Vincent Coubard 0:c6a8f2b3efb6 61
Vincent Coubard 0:c6a8f2b3efb6 62 **figure 4** Representation of the Led service using Master Control Panel 4.0.5
Vincent Coubard 0:c6a8f2b3efb6 63
Vincent Coubard 0:c6a8f2b3efb6 64 1. Open the write pannel of the *LED state* characteristic.
Vincent Coubard 0:c6a8f2b3efb6 65
Vincent Coubard 0:c6a8f2b3efb6 66 ![](img/write_characteristic.png)
Vincent Coubard 0:c6a8f2b3efb6 67
Vincent Coubard 0:c6a8f2b3efb6 68 **figure 5** How to read and write a characteristic value using Master Control Panel 4.0.5
Vincent Coubard 0:c6a8f2b3efb6 69
Vincent Coubard 0:c6a8f2b3efb6 70
Vincent Coubard 0:c6a8f2b3efb6 71 1. The characteristic accept a 1 byte value:
Vincent Coubard 0:c6a8f2b3efb6 72
Vincent Coubard 0:c6a8f2b3efb6 73 ![](img/write_pannel.png)
Vincent Coubard 0:c6a8f2b3efb6 74
Vincent Coubard 0:c6a8f2b3efb6 75 **figure 6** Write characteristic pannel using Master Control Panel 4.0.5
Vincent Coubard 0:c6a8f2b3efb6 76
Vincent Coubard 0:c6a8f2b3efb6 77 * `0x00`: LED ON
Vincent Coubard 0:c6a8f2b3efb6 78
Vincent Coubard 0:c6a8f2b3efb6 79 ![](img/LED_ON.png)
Vincent Coubard 0:c6a8f2b3efb6 80
Vincent Coubard 0:c6a8f2b3efb6 81 **figure 6** Write characteristic pannel to set the LED on using Master Control Panel 4.0.5
Vincent Coubard 0:c6a8f2b3efb6 82
Vincent Coubard 0:c6a8f2b3efb6 83
Vincent Coubard 0:c6a8f2b3efb6 84 * `0x01`: LED OFF
Vincent Coubard 0:c6a8f2b3efb6 85
Vincent Coubard 0:c6a8f2b3efb6 86 ![](img/LED_OFF.png)
Vincent Coubard 0:c6a8f2b3efb6 87
Vincent Coubard 0:c6a8f2b3efb6 88 **figure 6** Write characteristic pannel to set the LED off using Master Control Panel 4.0.5
Vincent Coubard 0:c6a8f2b3efb6 89
Vincent Coubard 0:c6a8f2b3efb6 90
Vincent Coubard 0:c6a8f2b3efb6 91 1. Toggle the LED characteristic value and see the LED turn ON or turn OFF according to the value you set.
Vincent Coubard 0:c6a8f2b3efb6 92
Vincent Coubard 0:c6a8f2b3efb6 93 If you can see the characteristic, and the LED is turned on/off as you toggle its value, the application is working properly.