1. It could be the entire infrastructure if all Low Power nodes are in direct radio range of the friend node and those are all the nodes in your mesh network. If you have nodes beyond the radio range of the friend node, you would need relay nodes in between. The proxy node is needed if you run a mobile phone as a provisioner for example. You can see 2.3.12 Topology of Mesh Profile 1.0.1 to understand further.

2. In theory, there is no limit of the number of Low Power nodes a friend node supports. The Bluetooth mesh stack allocates a friend queue in the friend node for storing messages for LPNs so this depends very much on the RAM available on BG21.

3. The maximum number of simultaneous BLE connections is 32.

1. It could be the entire infrastructure if all Low Power nodes are in direct radio range of the friend node and those are all the nodes in your mesh network. If you have nodes beyond the radio range of the friend node, you would need relay nodes in between. The proxy node is needed if you run a mobile phone as a provisioner for example. You can see 2.3.12 Topology of Mesh Profile 1.0.1 to understand more.

2. In theory, there is no limit of the number of Low Power nodes a friend node would support. The Bluetooth mesh stack allocates a friend queue in the friend node for storing messages for LPNs so this depends very much on the RAM available on BG21.

3. The maximum number of simultaneous BLE connections is 32.

You should use the BLE command sl_bt_user_manage_event_filter available in Gecko SDK v3.1.

See https://docs.silabs.com/bluetooth/3.1/group-sl-bt-user#gaabb7641d170c394f47f12a5d6f7594f3

I assume that you are talking about the notification function on the GATT server which is usually the slave (peripheral) device. The notification function is implemented in the BLE stack. The Notify section in this article explains how to use it: https://docs.silabs.com/bluetooth/latest/general/gatt-protocol/gatt-server-and-client-roles#notify

The BLE stack is provided as a static library so only the stack functions that are invoked by the application are pulled into the firmware. You can call gecko_stack_init() and individual BGAPI class initialization functions instead of gecko_init() to reduce the stack size.

See Section 4.2 of UG136: https://www.silabs.com/documents/public/user-guides/ug136-ble-c-soc-dev-guide.pdf

Hello,

I'm having problems to initialize my clocks. I'm confused if I'm initiating correctly. I'm using these lines of code:

// Bit [19] in MODULEINFO is the HFXOCALVAL:
// 1=No factory cal, use default XO tunning value in FW
// 0=Factory Cal, use XO tunning value in DI
#define DEVINFO_MODULEINFO_HFXOCALVAL_MASK 0x00080000UL
// Calibration value for HFXO CTUNE is at DEVINFO Offset 0x08
#define DEVINFO_MODULEINFO_CRYSTALOSCCALVAL \
    (*((uint16_t *) (uint32_t)(DEVINFO_BASE + 0x8UL)))
// [15:9] : (LFXOTUNING) Calibration for LFXO TUNING
// [8:0]  : (HFXOCTUNE) Calibration for HFXO CTUNE
#define DEVINFO_HFXOCTUNE_MASK 0x01FFUL

#define set_HFXO_CTUNE(val)         \
  do {                              \
    hfxoInit.ctuneXoAna = (val);    \
    hfxoInit.ctuneXiAna = (val);    \
  } while (0)

static void initMcu_clocks(void)
{
    // Initialize HFXO
    initHFXO();

    // Enable HFXO oscillator, and wait for it to be stable
    CMU_OscillatorEnable(cmuOsc_HFXO, true, true);
//    CMU_HFRCODPLLBandSet(cmuHFRCODPLLFreq_80M0Hz);
//    CMU_ClockSelectSet(cmuClock_SYSCLK, cmuSelect_HFRCODPLL);

    // Initialize LFXO
    initLFXO();
}

static void initLFXO(void) {
    CMU_LFXOInit_TypeDef lfxoInit = BSP_CLK_LFXO_INIT;
    lfxoInit.capTune = BSP_CLK_LFXO_CTUNE;
    CMU_LFXOInit(&lfxoInit);
    // Set system LFXO frequency
    SystemLFXOClockSet(BSP_CLK_LFXO_FREQ);
}

static void initHFXO(void)
{
    // Initialize HFXO
    // Use BSP_CLK_HFXO_INIT as last result (4th)
    CMU_HFXOInit_TypeDef hfxoInit = BSP_CLK_HFXO_INIT;
    // if Factory Cal exists in DEVINFO then use it above all (1st)
    if (0 == (DEVINFO->MODULEINFO & DEVINFO_MODULEINFO_HFXOCALVAL_MASK)) {
#if defined(_SILICON_LABS_32B_SERIES_1)
        set_HFXO_CTUNE(DEVINFO_MODULEINFO_CRYSTALOSCCALVAL);
#elif defined(_SILICON_LABS_32B_SERIES_2)
        set_HFXO_CTUNE(DEVINFO->MODXOCAL & _DEVINFO_MODXOCAL_HFXOCTUNEXIANA_MASK);
#endif
    }
    CMU_HFXOInit(&hfxoInit);

    // Set system HFXO frequency
    SystemHFXOClockSet(BSP_CLK_HFXO_FREQ);
}

Am I missing something? How to know the values of BSP_CLK_LFXO_CTUNE and BSP_CLK_HFXO_CTUNE correctly? These values can make the BLE doesn't work? I'm trying to use the Bluetooth stack.

This example code might help you:

https://www.silabs.com/community/wireless/bluetooth/knowledge-base.entry.html/2020/10/28/self_provisioningandconfigurationexample-J9sJ

See this KBA:  https://www.silabs.com/community/wireless/bluetooth/knowledge-base.entry.html/2019/10/11/using_mbedtls_withble-hEAg

NOTE

• Bluetooth Low Energy (BLE) Knowledge Base Articles are now moved to https://docs.silabs.com/bluetooth/latest/. They are not maintained any more.

• Bluetooth Mesh Knowledge Base Articles are still VALID and maintained here.

Introduction

This Knowledge Base Article (KBA) aims to act as a “master” KBA which keeps a curated index of all the Bluetooth related KBAs divided into logical categories for an easier and more convenient look-up. It may also include non-KBA content which is relevant for designing your Bluetooth application (e.g. app notes or web pages).

If you are just getting started with Silicon Labs Bluetooth solutions then your starting point should be QSG139: Getting Started with Bluetooth® Software Development. At the end of that document you are presented with the flowchart below which shows what documents should be read and in which order. Additionally you can check out our Bluetooth Training page for more training material.

Knowledge Base Articles List

The content listed below is grouped together into categories to make it easier for you to find what you are looking for. Want to know more about security, or looking for a peripheral example, then head down to the right section and see what KBAs or other relevant content has been created under those topics.

Each category has an associated index number and each individual KBA has its own index number within the category. The KBA's are prefixed with KBA_BT_AABB where AA is the category index and BB is the KBA index within that category. The category index numbers are as follows:

• [01] Bluetooth - General
• [02] Bluetooth - Advertising
• [03] Bluetooth - Stack features
• [04] Bluetooth - Performance
• [05] Bluetooth - Bluetooth Mesh
• [06] Bootloading - General
• [07] Bootloading - UART DFU
• [08] Bootloading - OTA DFU
• [09] Application Examples
• [10] Peripheral Examples
• [11] Security
• [12] Tools
• [13] Hardware
• [14] Migration
• [15] Mobile
• [16] NCP

Note: Do you want to get automatic notifications when new content is added to the list? Just click the Follow button in upper right corner to subscribe to email notifications. We will make comments when new content is created to trigger those notifications.

[01] Bluetooth General

• KBA_BT_0101: Selecting Your Blue Gecko SoC/Module
• KBA_BT_0102: BLE Basics (master/slave, GATT client/server, data RX/TX)
• KBA_BT_0103: Understanding the Bluetooth Connection Process
• KBA_BT_0104: Acknowledged vs Unacknowledged GATT operations 
• KBA_BT_0105: Bluetooth 5 Features 
• KBA_BT_0106: Bluetooth SIG Resources 
• KBA_BT_0107: Bluetooth Stack Operations Flowcharts

[02] Bluetooth - Advertising

• KBA_BT_0201: Bluetooth advertising data basics 
• KBA_BT_0202: Bluetooth advertising using manufacturer specific data 
• KBA_BT_0203: Providing Extra Data by Scan Response 
• KBA_BT_0204: Using scan request reporting
• KBA_BT_0205: Advertisement Constructor 
• KBA_BT_0206: Extended Advertising Example 
• KBA_BT_0207: Periodic Advertising
• KBA_BT_0208: Chained Advertisements

[03] Bluetooth - Stack features

• KBA_BT_0301: LE Coded PHY on EFR32xG13
• KBA_BT_0302: Advertising and Scanning with LE Coded PHY 
• KBA_BT_0304: Different characteristic value types 
• KBA_BT_0305: Handling GPIO Interrupts using External Signals 
• KBA_BT_0306: Using the lazy soft timer
• KBA_BT_0307: Enabling TX/RX activity indicator pins in BLE SDK 2.4.0 and later 
• KBA_BT_0308: Polymorphic GATT 
• KBA_BT_0309: How to save float values (or any arbitrary data) in PS keys
• KBA_BT_0310: Changes to the le_gap class of API functions
• KBA_BT_0311: Whitelisting
• KBA_BT_0312: Service Change Indications 
• KBA_BT_0313: GATT Caching

[04] Bluetooth - Performance

• KBA_BT_0401: Optimizing Current Consumption in Bluetooth Low Energy Devices 
• KBA_BT_0402: EM3 and EM4S for non-connectable advertising 
• KBA_BT_0403: Using Energy Modes with Bluetooth Stack 
• KBA_BT_0404: Throughput with Bluetooth Low Energy technology
• KBA_BT_0405: Bluetooth Tx power settings
• KBA_BT_0406: Adaptive Frequency Hopping
• KBA_BT_0407: Bluetooth Radio Task Priorities
• KBA_BT_0408: Current consumption during advertising with different Tx power setting
• KBA_BT_0409: Using the PLFRCO as low-frequency clock source
• KBA_BT_0410: TX power limitations for regulatory compliance (ETSI, FCC)

[05] Bluetooth - Bluetooth Mesh

• KBA_BT_0501: BT Mesh embedded provisioner example 
• KBA_BT_0502: Bluetooth Mesh Vendor Specific Model Example 
• KBA_BT_0503: Advertising Sets Used by the Bluetooth Mesh Stack
• KBA_BT_0504: Adding custom advertising to the Bluetooth mesh examples
• KBA_BT_0505: Bluetooth Mesh Training resources
• KBA_BT_0506: Minimalistic OnOff client for testing Bluetooth Mesh on custom board
• KBA_BT_0507: Bluetooth Mesh Host Switch Example
• KBA_BT_0508: Scanning BLE beacons in Bluetooth Mesh mode 
• KBA_BT_0509: Bluetooth Mesh Host Provisioner
• KBA_BT_0510: Blacklisting Nodes From Bluetooth Mesh Network
• KBA_BT_0512: Bluetooth Mesh Proxy Client Example
• KBA_BT_0513: IV Update & Recovery Procedure and Sequence Number Storing Strategy
• KBA_BT_0515: Bluetooth Mesh Mobile - Import/Export Functionalities Concepts
• KBA_BT_0517: Bluetooth Mesh Node Reset Procedure
• KBA_BT_0518: Self provisioning and configuration example

[06] Bootloading - General

• KBA_BT_0601: Why Doesn't My Sample Application Run?
• KBA_BT_0602: Bootloader changes in BLE SDK
• KBA_BT_0603: Adding Gecko Bootloader to Bluetooth projects
• KBA_BT_0604: Switching between firmware images using Internal Storage Bootloader
• KBA_BT_0605: Upgrading Gecko Bootloader
• KBA_BT_0606: Upgrading Gecko Bootloader with Slot address change
• KBA_BT_0607: Adding metadata to GBL files 
• KBA_BT_0608: Factory programmed firmware of Bluetooth devices

[07] Bootloading - UART DFU

• KBA_BT_0701: Upgrading from factory firmware (v2.0.0) and from Bluetooth SDK v2.1.x with UART DFU type legacy bootloader
• KBA_BT_0702: UART DFU - Upgrading BGM111 by EFM32PG example 

[08] Bootloading - OTA DFU

• KBA_BT_0801: Using Blue Gecko app OTA
• KBA_BT_0802: Uploading images to internal/external flash using OTA DFU 
• KBA_BT_0803: Bluetooth OTA updates using customized advertising data
• KBA_BT_0804: Secure OTA DFU
• KBA_BT_0805: Setting Bluetooth Address as device name in OTA 
• KBA_BT_0806: Using BLED112 to do Over-the-Air update of BGMxxx 
• KBA_BT_0807: Implementing OTA firmware update in the user application
• KBA_BT_0808: OTA options for NCP-based designs 

[09] Application Examples

• KBA_BT_0901: Bluetooth SoC-Empty example
• KBA_BT_0902: How to use Voice over Bluetooth Low Energy example for Thunderboard Sense
• KBA_BT_0903: SPP-over-BLE example 
• KBA_BT_0904: Creating an Eddystone-URL Beacon 
• KBA_BT_0905: SPP client example using BLED112 dongle 
• KBA_BT_0906: Multi-Slave Multi-Master Dual-Topology example 
• KBA_BT_0907: Parallel handling of multiple slaves with Bluetooth stack 
• KBA_BT_0908: Using RTCC as Timer or Calendar while running BLE stack 
• KBA_BT_0909: Scheduling application tasks while running BLE stack
• KBA_BT_0910: Using the UD flash in the Bluetooth C SDK 
• KBA_BT_0911: Midi over BLE 
• KBA_BT_0912: Control LEDs on a Wireless Starter Kit from a Mobile App 
• KBA_BT_0913: BLE Central and GATT client example - working with an Android app 
• KBA_BT_0914: ANCS 
• KBA_BT_0915: Throughput Tester Example 
• KBA_BT_0916: Working with Long Characteristic Values 
• KBA_BT_0917: Implementing wireless direct test mode (DTM) 
• KBA_BT_0919: Using EM3 or EM4 energy mode in a Bluetooth beacon app 
• KBA_BT_0920: Bluetooth Device Tracking with Tile
• KBA_BT_0921: Using Mbedtls with BLE 

[10] Peripheral Examples

• KBA_BT_1001: Using the LEUART 
• KBA_BT_1002: Using Low Energy Timers 
• KBA_BT_1003: Using accelerometer found in the WSTK expansion board 
• KBA_BT_1004: Hardware Timers with EFR32xG1x 
• KBA_BT_1005: Reporting Battery Voltage over BLE 
• KBA_BT_1006: Thermometer example with EFR32 internal temperature sensor 
• KBA_BT_1007: Enable LCD screen on WSTK 
• KBA_BT_1008: Watchdog on BGM111 (and other Blue Gecko modules / boards) 
• KBA_BT_1009: Waking from Deep Sleep Using RF Sense 
• KBA_BT_1010: Push buttons and interrupts in a Bluetooth project 
• KBA_BT_1011: How can I extend the Bluetooth examples with UART functionality? 
• KBA_BT_1012: Adding Watchdog in NCP Mode

Additional Resources

• MCU Peripheral Examples on GitHub (also includes EFR32)

[11] Security

• KBA_BT_1101: Using Bluetooth security features in Silicon Labs Bluetooth SDK
• KBA_BT_1102: Pairing Processes
• KBA_BT_1103: Application Layer Security 
• KBA_BT_1104: The New Bond Replacement Algorithm
• KBA_BT_1105: How to handle missing bonding keys 
• KBA_BT_1106: OOB introduction and example 
• KBA_BT_1107: Secure connection with serial communication between two BGM modules 
• KBA_BT_1108: Authenticating Bluetooth Devices with no User Interface 

[12] Tools

• KBA_BT_1201: Condensed Bluetooth SDK revision history (2.0.0 and later)
• KBA_BT_1202: Building C++ BLE projects
• KBA_BT_1203: Creating projects for EFR32BG on a custom board
• KBA_BT_1204: How to flash BGM11x or EFR32BG from command line?
• KBA_BT_1205: Programming an external BGM111 using the WSTK
• KBA_BT_1206: Log System
• KBA_BT_1207: Event and Error Checking 
• KBA_BT_1208: Using virtual COM port (VCOM)
• KBA_BT_1209: Debugging BGTool not being able to communicate with NCP target.
• KBA_BT_1210: Connect Custom board to Simplicity Studio using JTAG/SWD.

Additional Resources

• Simplicity Studio now Treats Bluetooth Modules as Parts

[13] Hardware

• KBA_BT_1301: How to find schematics and other documentation for radio boards?
• KBA_BT_1302: Supplying EFR32 PAVDD from 3.3V
• KBA_BT_1303: Enabling LNA on MGM12P for Bluetooth usage
• KBA_BT_1304: Antenna tuning for BGM12x (coin-cell usage example)
• KBA_BT_1305: Quartz Crystals, MEMS Oscillators, and Phase Noise for BLE Applications
• KBA_BT_1306: TX Power Levels 
• KBA_BT_1307: What is a STEP file and how to obtain a STEP file for Silicon Labs IOT products?
• KBA_BT_1308: Saving CTUNE value as manufacturing token
• KBA_BT_1309: Design and Assembly guidelines when using xGM parts based System in Package (SiP)

Additional Resources

• Debugging and Programming Interfaces for Custom Designs
• Production Programming Options for Silicon Labs Devices
• RF Range Calculator
• Driving FEMs (and PAs and LNAs) on EFR32

[14] Migration

• KBA_BT_1401: Updating NCP projects to SDK 2.4.x
• KBA_BT_1402: Bluetooth Smart SDK Migration Guide From V2.0.1 to V2.1.x
• KBA_BT_1403: Migrating Simplicity Studio projects from Bluetooth SDK 2.1.1 to 2.3.1
• KBA_BT_1404: Migrating Simplicity Studio projects from Bluetooth SDK 2.3.x to 2.4.x
• KBA_BT_1405: Migration guide to Bluetooth SDK 2.7.x
• KBA_BT_1406: Migrating Bluetooth Projects between SDK Releases

[15] Mobile

• KBA_BT_1501: BLE devices on iOS Bluetooth Settings page
• KBA_BT_1502: Evaluating SPP-over-BLE example using BLE1xx cable replacement app 
• KBA_BT_1503: iOS 9.1 with respect to Bluetooth LE
• KBA_BT_1504: Mobile Devices used for Interoperability Testing
• KBA_BT_1505: Selecting suitable connection parameters for iOS 
• KBA_BT_1506: How to find the Bluetooth 5 feature status of a listed device such as a smartphone

[16] NCP

• KBA_BT_1602: NCP Host Implementation and Example 
• KBA_BT_1603: Local Event Handling on Bluetooth NCP