The Silicon Labs BLED112 Bluetooth Low Energy USB dongle is a single-mode USB device enabling Bluetooth Low Energy connectivity for PCs and other devices having a USB port. The dongle integrates all Bluetooth 4.0 single mode features and can be used with the Bluetooth Framework on any Windows platform.
As the BLED112 is a single-mode Bluetooth Low Energy module, it does not support any Bluetooth Classic features. BLED112 works as a GATT central (client) device. It also can discover Bluetooth LE devices and receive and broadcast Bluetooth LE advertisements. BLED112 supports passkey notification and passkey request pairing.
Why you need BLED112
The main advantage of using the BLED112 dongle is that it gives you full control over the GATT communication. As the dongle is not supported by the Windows native Bluetooth driver, it allows communication with GATT-enabled devices that do not work well with the Microsoft Bluetooth driver. For example, if you try to work with a Bluetooth LE HID device, the Microsoft Bluetooth driver does not allow you to do that. But the BLED112 does. The BLED112 can connect to such devices directly without needing to install a BLE HID driver and without blocking the device by the OS.
As you know, the Microsoft Bluetooth driver does not allow you to add any data types in the BLE advertisement. And if you need it, the BLED112 is the way to do that. It has just a few limitations on possible BLE advertisement data and does not limit you a lot.
The BLED112 helps in case you need to work with a GATT-enabled device that uses non-optimal connection parameters, and the communication with such a device is very slow. The first idea is to try to change the Bluetooth LE connection parameters to increase the communication speed. However, you may not have access to the device's firmware. And this is the real problem if your application must run on Windows 10. The only solution is to use the BLED112 USB dongle. This device allows you to change the connection parameters on any Windows platform, including Windows XP.
Sometimes you may need to connect to a few GATT-enabled Bluetooth LE devices at the same time. The Bluetooth hardware limits the number of simultaneous connections to just a few, usually up to 3 or 5. And the first idea on how to fix it is to use more than one Bluetooth dongle. But that is not possible with standard Windows Bluetooth drivers. But possible with the BLED112 dongle. You can connect as many BLED112s as you want. The Bluetooth Framework does not limit how many modules you use.
And of course, if your application must run on a legacy Windows platform such as Windows XP or Windows Vista, or any other that does not support Bluetooth LE technology, the BLED112 is the solution. The Bluetooth Framework allows you to use Bluetooth LE on any Windows platform with the BLED112 USB Bluetooth dongle.
Connecting BLED112
Once plugged in, the BLED112 appears as a COM port in the system. Windows 10 and above installs the BLED112 driver automatically. Windows XP, Windows 7, and sometimes Windows 8 do not install the BLED112 driver automatically, and you need to download and install it manually. You can find the BLED112 driver by this link. You do not need any additional SDKs or drivers to be able to use the BLED112 Bluetooth USB dongle with the Bluetooth Framework.