BLE_Button is a BLE service template. It handles a read-only characteristic with a simple input (boolean values). The input's source is the button on the board itself - the characteristic's value changes when the button is pressed or released. The canonical source for this example lives at https://github.com/ARMmbed/mbed-os-example-ble/tree/master/BLE_Button

BLE_Button is a BLE service template. It handles a read-only characteristic with a simple input (boolean values). The input's source is the button on the board itself - the characteristic's value changes when the button is pressed or released.

The template covers:

  • Setting up advertising and connection modes.
  • Creating an input characteristic: read-only, boolean, with notifications.
  • Constructing a service class and adding it to the BLE stack.
  • Assigning UUIDs to the service and its characteristic.
  • Pushing notifications when the characteristic's value changes.

Running the application

Requirements

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 :

- nRF Master Control Panel for Android.

- LightBlue for iPhone.

Hardware requirements are in the main readme.

Building instructions

Building with mbed CLI

If you'd like to use mbed CLI to build this, then you should refer to the main readme. The instructions here relate to using the developer.mbed.org Online Compiler

In order to build this example in the mbed Online Compiler, first import the example using the ‘Import’ button on the right hand side.

Next, select a platform to build for. This must either be a platform that supports BLE, for example the NRF51-DK, or one of the following:

List of platforms supporting Bluetooth Low Energy

Or you must also add a piece of hardware and the supporting library that includes a Bluetooth Low Energy driver for that hardware, for example the K64F or NUCLEO_F401RE with the X-NUCLEO-IDB05A1

List of components supporting Bluetooth Low Energy.

Once you have selected your platform, compile the example and drag and drop the resulting binary onto your board.

For general instructions on using the mbed Online Compiler, please see the mbed Handbook

Checking for success

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.

  • Build the application and install it on your board as explained in the building instructions.
  • Open the BLE scanner on your phone.
  • Start a scan.

https://developer.mbed.org/teams/mbed-os-examples/code/mbed-os-example-ble-Button/raw-file/3fe9d5124576/img/start_scan.png

figure 1 How to start scan using nRF Master Control Panel 4.0.5

  • Find your device; it should appear with the name `Button` in the scanner.

https://developer.mbed.org/teams/mbed-os-examples/code/mbed-os-example-ble-Button/raw-file/3fe9d5124576/img/scan_results.png

figure 2 Scan results using nRF Master Control Panel 4.0.5

  • Establish a connection with the device.

https://developer.mbed.org/teams/mbed-os-examples/code/mbed-os-example-ble-Button/raw-file/3fe9d5124576/img/connection.png

figure 3 How to establish a connection using Master Control Panel 4.0.5

  • Discover the services and the characteristics on the device. The Button service has the UUID `0xA000` and includes the Button 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.

https://developer.mbed.org/teams/mbed-os-examples/code/mbed-os-example-ble-Button/raw-file/3fe9d5124576/img/discovery.png

figure 4 Representation of the Button service using Master Control Panel 4.0.5

  • Register for the notifications sent by the button state characteristic then the scanner will automatically receive a notification containing the new state of the button every time the state of the button changes.

https://developer.mbed.org/teams/mbed-os-examples/code/mbed-os-example-ble-Button/raw-file/3fe9d5124576/img/register_to_notifications.png

figure 5 How to register to notifications using Master Control Panel 4.0.5

  • Pressing Button 1 on your board updates the state of the button and sends a notification to the scanner. The new state of the button characteristic value should be equal to 0x01.

https://developer.mbed.org/teams/mbed-os-examples/code/mbed-os-example-ble-Button/raw-file/3fe9d5124576/img/button_pressed.png

figure 6 Notification of button pressed using Master Control Panel 4.0.5

  • Releasing Button 1 on your board updates the state of the button and sends a notification to the scanner. The new state of the button characteristic value should be equal to 0x00.

https://developer.mbed.org/teams/mbed-os-examples/code/mbed-os-example-ble-Button/raw-file/3fe9d5124576/img/button_depressed.png

figure 7 Notification of button depressed using Master Control Panel 4.0.5

Revisions of mbed-os.lib

Revision Date Message Actions
86:1be8792a718f 2019-10-18 Merge pull request #268 from trowbridgec/add-ep-agora File  Diff  Annotate
85:87025316b435 2019-08-15 Merge pull request #252 from donatieng/mbed_os_update File  Diff  Annotate
82:ef5eb99731c9 2019-02-27 Updating mbed-os to mbed-os-5.11.5 File  Diff  Annotate
81:7c05ae04bdda 2019-02-25 Merge pull request #217 from adbridge/master File  Diff  Annotate
80:242119fdf64a 2019-02-13 Updating mbed-os to mbed-os-5.11.2 File  Diff  Annotate
79:fd8cb5e94fd9 2019-01-14 Merge pull request #207 from adbridge/master File  Diff  Annotate
78:f06ac76a8f6d 2019-01-14 Merge pull request #208 from ARMmbed/mbed-os-5.11.0-oob File  Diff  Annotate
77:ab380ce47fe1 2018-12-14 Updating mbed-os to mbed-os-5.10.4 File  Diff  Annotate
75:c9564f761dbe 2018-11-07 Merge pull request #189 from ARMmbed/donatieng-patch-1 File  Diff  Annotate
74:71cc8b73be25 2018-10-22 Merge pull request #187 from cmonr/master File  Diff  Annotate
73:7c8d26907858 2018-09-26 Merge pull request #183 from ARMmbed/mbed-os-5.10.0-oob File  Diff  Annotate
71:fcfe2169766d 2018-08-29 Merge pull request #172 from 0xc0170/master File  Diff  Annotate
70:4cfa7179383b 2018-08-23 Updating mbed-os to mbed-os-5.9.5 File  Diff  Annotate
69:4240a1535b46 2018-08-08 Merge pull request #168 from cmonr/master File  Diff  Annotate
68:577cd5a90877 2018-07-18 Merge pull request #166 from cmonr/master File  Diff  Annotate
67:df327fb6fbf5 2018-07-06 Merge pull request #163 from adbridge/master File  Diff  Annotate
66:562421c85792 2018-06-22 Merge pull request #160 from adbridge/master File  Diff  Annotate
65:dac86cc455e9 2018-06-20 Merge pull request #159 from ARMmbed/mbed-os-5.9.0-oob File  Diff  Annotate
64:f4807c632195 2018-06-11 Merge pull request #158 from adbridge/master File  Diff  Annotate
63:612725a2da42 2018-06-05 Merge pull request #151 from paul-szczepanek-arm/privacy File  Diff  Annotate
62:195115be62ba 2018-04-04 Merge pull request #141 from adbridge/master File  Diff  Annotate
61:b5b53d2b7b49 2018-04-04 Merge pull request #142 from ARMmbed/mbed-os-5.8.0-oob File  Diff  Annotate
60:b0ccdd3a8109 2018-03-23 Merge pull request #139 from cmonr/master File  Diff  Annotate
59:05d4800c81d4 2018-03-23 Merge pull request #137 from adbridge/master File  Diff  Annotate
58:e3a894988713 2018-02-13 Merge pull request #135 from adbridge/master File  Diff  Annotate
56:a1c4a2f43250 2018-01-31 Merge pull request #134 from cmonr/master File  Diff  Annotate
55:6ae4c68e2ae6 2018-01-17 Merge pull request #133 from adbridge/master File  Diff  Annotate
54:67ce197bf409 2018-01-09 Merge pull request #129 from adbridge/master File  Diff  Annotate
52:41f215929fcb 2017-12-20 Merge pull request #126 from ARMmbed/mbed-os-5.7.0-oob File  Diff  Annotate
51:89d1257a42b7 2017-12-05 Merge pull request #119 from adbridge/master File  Diff  Annotate
50:73af5a8856a8 2017-11-23 Merge pull request #115 from adbridge/master File  Diff  Annotate
49:9da63fbbde83 2017-11-07 Merge pull request #113 from adbridge/master File  Diff  Annotate
48:9bb7216012bd 2017-11-03 Merge pull request #110 from 0xc0170/master File  Diff  Annotate
46:eb859fddbf1f 2017-10-11 Merge pull request #108 from adbridge/master File  Diff  Annotate
45:d38acaddede4 2017-09-29 Merge pull request #106 from 0xc0170/master File  Diff  Annotate
44:8ea4bcef5c74 2017-09-20 Merge pull request #103 from ARMmbed/5.6_sanity File  Diff  Annotate
43:0202a49aa86c 2017-09-08 Merge pull request #102 from adbridge/master File  Diff  Annotate
42:517f855d8f63 2017-08-08 Merge pull request #100 from 0xc0170/master File  Diff  Annotate
40:d840e94a0e7b 2017-07-19 Merge pull request #97 from 0xc0170/master File  Diff  Annotate
38:7d3a99d6bea1 2017-07-11 Merge pull request #93 from adbridge/master File  Diff  Annotate
37:95eeffdbf1ed 2017-06-22 Merge pull request #89 from adbridge/master File  Diff  Annotate
35:dafdbff49057 2017-06-20 Merge pull request #88 from adbridge/master File  Diff  Annotate
33:775e958a34e9 2017-06-08 Merge pull request #82 from adbridge/master File  Diff  Annotate
32:9671c1c20904 2017-05-25 Merge pull request #81 from adbridge/master File  Diff  Annotate
31:c5d506107459 2017-05-10 Merge pull request #79 from adbridge/master File  Diff  Annotate
29:861204153da9 2017-05-09 Merge pull request #77 from 0xc0170/master File  Diff  Annotate
28:f3b0440a1d89 2017-04-05 Merge pull request #70 from 0xc0170/master File  Diff  Annotate
25:0621ad081aca 2017-03-14 Merge pull request #68 from adbridge/master File  Diff  Annotate
24:6792a244c84e 2017-03-09 Merge pull request #66 from ARMmbed/oob_test_mbed-os-5.4 File  Diff  Annotate
23:be5f0612fe27 2017-03-01 Merge pull request #55 from adbridge/master File  Diff  Annotate
21:57833ebf2112 2017-02-15 Merge pull request #52 from 0xc0170/master File  Diff  Annotate
20:ebfc41caf0d0 2017-02-02 Merge pull request #48 from adbridge/master File  Diff  Annotate
19:764b505468b2 2017-01-26 Merge pull request #46 from adbridge/master File  Diff  Annotate
18:4d6a1a181c22 2016-12-15 Update mbed-os revision to mbed-os 5.3.0. File  Diff  Annotate
17:b6f5425afcb0 2016-12-15 Merge pull request #42 from ARMmbed/mbed-os-5.3.0-rc3 File  Diff  Annotate
16:644fc574aada 2016-10-28 Updating mbed-os to mbed-os-5.2.1 File  Diff  Annotate
15:54be53eea95e 2016-10-24 Updating mbed-os to mbed-os-5.2.0 File  Diff  Annotate
14:014670ad5e18 2016-10-24 Merge pull request #32 from ARMmbed/oob File  Diff  Annotate
13:3d3f488da1bc 2016-10-05 Updating mbed-os to mbed-os-5.1.5 File  Diff  Annotate
12:6674f9fb8790 2016-09-16 Updating mbed-os to mbed-os-5.1.4 File  Diff  Annotate