mbed-os-examples / Mbed OS mbed-os-example-ble-LEDBlinker

This example demonstrates using the GattClient API to control BLE client devices. The canonical source for this example lives at https://github.com/ARMmbed/mbed-os-example-ble/tree/master/BLE_LEDBlinker

BLE LED Blinker

This example demonstrates using the ``GattClient`` API to control BLE client devices.

The example uses two applications running on two different devices:

  • The first device - the central - runs the application ``BLE_LEDBlinker`` from this repository. This application sends an on/off toggle over BLE.
  • The second device - the peripheral - runs the application ``BLE_LED`` to respond to the toggle.

The toggle simply turns the LED on the peripheral device on and off.

Running the application

Requirements

Hardware requirements are in the main readme.

This example requires *two* devices.

Building instructions

You will need to build both applications and flash each one to a different board.

Please note: The application BLE_LEDBlinker in this repository initiate a connection to all ble devices which advertise "LED" as complete local name. By default, the application BLE_LED advertises "LED" as complete local name. If you change the local name advertised by the application BLE_LED you should reflect your change in this application by changing the value of the constant PEER_NAME in main.cpp.

Tip: You may notice that the application also checks the LED characteristic's UUID; you don't need to change this parameter's value, because it already matches the UUID provided by the second application, BLE_LED.

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

  • Build both applications and install one on each device, as explained in the building instructions.
  • The LED number two of the device running ``BLE_LED`` should blink.

Monitoring the application through a serial port

You can run ``BLE_LEDBlinker`` and see that it works properly by monitoring its serial output.

You need a terminal program to listen to the output through a serial port. You can download one, for example:

  • Tera Term for Windows.
  • CoolTerm for Mac OS X.
  • GNU Screen for Linux.

To see the application's output:

  • Check which serial port your device is connected to.
  • Run a terminal program with the correct serial port and set the baud rate to 9600. For example, to use GNU Screen, run: ``screen /dev/tty.usbmodem1412 9600``.
  • The application should start printing the toggle's value to the terminal.

Note: ``BLE_LEDBlinker`` will not run properly if the ``BLE_LED`` application is not running on a second device. The terminal will show a few print statements, but you will not be able to see the application in full operation.

source/pretty_printer.h@81:653db77bffd4, 2019-08-15 (annotated)

Committer:
mbed_official
Date:
Thu Aug 15 17:02:05 2019 +0100
Revision:
81:653db77bffd4
Parent:
75:1a8d19363522 
Merge pull request #252 from donatieng/mbed_os_update



Update Master branch to use Mbed OS 5.13.1

.

Commit copied from https://github.com/ARMmbed/mbed-os-example-ble

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbed_official 75:1a8d19363522 1 /* mbed Microcontroller Library
mbed_official 75:1a8d19363522 2 * Copyright (c) 2018 ARM Limited
mbed_official 75:1a8d19363522 3 *
mbed_official 75:1a8d19363522 4 * Licensed under the Apache License, Version 2.0 (the "License");
mbed_official 75:1a8d19363522 5 * you may not use this file except in compliance with the License.
mbed_official 75:1a8d19363522 6 * You may obtain a copy of the License at
mbed_official 75:1a8d19363522 7 *
mbed_official 75:1a8d19363522 8 * http://www.apache.org/licenses/LICENSE-2.0
mbed_official 75:1a8d19363522 9 *
mbed_official 75:1a8d19363522 10 * Unless required by applicable law or agreed to in writing, software
mbed_official 75:1a8d19363522 11 * distributed under the License is distributed on an "AS IS" BASIS,
mbed_official 75:1a8d19363522 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
mbed_official 75:1a8d19363522 13 * See the License for the specific language governing permissions and
mbed_official 75:1a8d19363522 14 * limitations under the License.
mbed_official 75:1a8d19363522 15 */
mbed_official 75:1a8d19363522 16
mbed_official 75:1a8d19363522 17 #include <mbed.h>
mbed_official 75:1a8d19363522 18 #include "ble/BLE.h"
mbed_official 75:1a8d19363522 19
mbed_official 75:1a8d19363522 20 inline void print_error(ble_error_t error, const char* msg)
mbed_official 75:1a8d19363522 21 {
mbed_official 75:1a8d19363522 22 printf("%s: ", msg);
mbed_official 75:1a8d19363522 23 switch(error) {
mbed_official 75:1a8d19363522 24 case BLE_ERROR_NONE:
mbed_official 75:1a8d19363522 25 printf("BLE_ERROR_NONE: No error");
mbed_official 75:1a8d19363522 26 break;
mbed_official 75:1a8d19363522 27 case BLE_ERROR_BUFFER_OVERFLOW:
mbed_official 75:1a8d19363522 28 printf("BLE_ERROR_BUFFER_OVERFLOW: The requested action would cause a buffer overflow and has been aborted");
mbed_official 75:1a8d19363522 29 break;
mbed_official 75:1a8d19363522 30 case BLE_ERROR_NOT_IMPLEMENTED:
mbed_official 75:1a8d19363522 31 printf("BLE_ERROR_NOT_IMPLEMENTED: Requested a feature that isn't yet implement or isn't supported by the target HW");
mbed_official 75:1a8d19363522 32 break;
mbed_official 75:1a8d19363522 33 case BLE_ERROR_PARAM_OUT_OF_RANGE:
mbed_official 75:1a8d19363522 34 printf("BLE_ERROR_PARAM_OUT_OF_RANGE: One of the supplied parameters is outside the valid range");
mbed_official 75:1a8d19363522 35 break;
mbed_official 75:1a8d19363522 36 case BLE_ERROR_INVALID_PARAM:
mbed_official 75:1a8d19363522 37 printf("BLE_ERROR_INVALID_PARAM: One of the supplied parameters is invalid");
mbed_official 75:1a8d19363522 38 break;
mbed_official 75:1a8d19363522 39 case BLE_STACK_BUSY:
mbed_official 75:1a8d19363522 40 printf("BLE_STACK_BUSY: The stack is busy");
mbed_official 75:1a8d19363522 41 break;
mbed_official 75:1a8d19363522 42 case BLE_ERROR_INVALID_STATE:
mbed_official 75:1a8d19363522 43 printf("BLE_ERROR_INVALID_STATE: Invalid state");
mbed_official 75:1a8d19363522 44 break;
mbed_official 75:1a8d19363522 45 case BLE_ERROR_NO_MEM:
mbed_official 75:1a8d19363522 46 printf("BLE_ERROR_NO_MEM: Out of Memory");
mbed_official 75:1a8d19363522 47 break;
mbed_official 75:1a8d19363522 48 case BLE_ERROR_OPERATION_NOT_PERMITTED:
mbed_official 75:1a8d19363522 49 printf("BLE_ERROR_OPERATION_NOT_PERMITTED");
mbed_official 75:1a8d19363522 50 break;
mbed_official 75:1a8d19363522 51 case BLE_ERROR_INITIALIZATION_INCOMPLETE:
mbed_official 75:1a8d19363522 52 printf("BLE_ERROR_INITIALIZATION_INCOMPLETE");
mbed_official 75:1a8d19363522 53 break;
mbed_official 75:1a8d19363522 54 case BLE_ERROR_ALREADY_INITIALIZED:
mbed_official 75:1a8d19363522 55 printf("BLE_ERROR_ALREADY_INITIALIZED");
mbed_official 75:1a8d19363522 56 break;
mbed_official 75:1a8d19363522 57 case BLE_ERROR_UNSPECIFIED:
mbed_official 75:1a8d19363522 58 printf("BLE_ERROR_UNSPECIFIED: Unknown error");
mbed_official 75:1a8d19363522 59 break;
mbed_official 75:1a8d19363522 60 case BLE_ERROR_INTERNAL_STACK_FAILURE:
mbed_official 75:1a8d19363522 61 printf("BLE_ERROR_INTERNAL_STACK_FAILURE: internal stack faillure");
mbed_official 75:1a8d19363522 62 break;
mbed_official 75:1a8d19363522 63 }
mbed_official 75:1a8d19363522 64 printf("\r\n");
mbed_official 75:1a8d19363522 65 }
mbed_official 75:1a8d19363522 66
mbed_official 75:1a8d19363522 67 /** print device address to the terminal */
mbed_official 75:1a8d19363522 68 void print_address(const uint8_t *addr)
mbed_official 75:1a8d19363522 69 {
mbed_official 75:1a8d19363522 70 printf("%02x:%02x:%02x:%02x:%02x:%02x\r\n",
mbed_official 75:1a8d19363522 71 addr[5], addr[4], addr[3], addr[2], addr[1], addr[0]);
mbed_official 75:1a8d19363522 72 }
mbed_official 75:1a8d19363522 73
mbed_official 75:1a8d19363522 74 inline void print_mac_address()
mbed_official 75:1a8d19363522 75 {
mbed_official 75:1a8d19363522 76 /* Print out device MAC address to the console*/
mbed_official 75:1a8d19363522 77 Gap::AddressType_t addr_type;
mbed_official 75:1a8d19363522 78 Gap::Address_t address;
mbed_official 75:1a8d19363522 79 BLE::Instance().gap().getAddress(&addr_type, address);
mbed_official 75:1a8d19363522 80 printf("DEVICE MAC ADDRESS: ");
mbed_official 75:1a8d19363522 81 print_address(address);
mbed_official 75:1a8d19363522 82 }
mbed_official 75:1a8d19363522 83
mbed_official 75:1a8d19363522 84 inline const char* phy_to_string(Gap::Phy_t phy) {
mbed_official 75:1a8d19363522 85 switch(phy.value()) {
mbed_official 75:1a8d19363522 86 case Gap::Phy_t::LE_1M:
mbed_official 75:1a8d19363522 87 return "LE 1M";
mbed_official 75:1a8d19363522 88 case Gap::Phy_t::LE_2M:
mbed_official 75:1a8d19363522 89 return "LE 2M";
mbed_official 75:1a8d19363522 90 case Gap::Phy_t::LE_CODED:
mbed_official 75:1a8d19363522 91 return "LE coded";
mbed_official 75:1a8d19363522 92 default:
mbed_official 75:1a8d19363522 93 return "invalid PHY";
mbed_official 75:1a8d19363522 94 }
mbed_official 75:1a8d19363522 95 }