Development with HCI HCI It is possible to program the Vela IF820 module with a specific HCI firmware version. The module can then be used as an HCI Bluetooth controller exposing an HCI UART interface. Obtaining the HCI Firmware Download the Vela IF820 HCI firmware at the following link: Vela IF820 HCI firmware Programming the HCI Firmware Loading the HCI firmware requires the AIROC Bluetooth Test and Debug Tool for Windows from Infineon which can be downloaded at the following link: AIROC™ Bluetooth® Test and Debug Tool The tool will start up with the below window and pressing “Select Device” allows to choose the proper device for the next steps. See here for information on determining the HCI COM port ID. Selecting Program Device from the Tools menu will start the programming dialog. In the new window select the target device as CYW20819/20, the HCI COM port and baud rate. See below screenshot for proper settings and which firmware file goes into what field. Using the Vela IF820 HCI Module on Linux Linux usually comes with all necessary tools preinstalled. Those are: BlueZ (Official Linux Bluetooth/LE stack) hciconfig, hciattach, hcitool (command line utility for configuring HCI devices and doing basic tasks) Connect the Vela IF820 to your Linux PC. The IF820 USB dongle version can be directly plugged into a USB port. When using an IF820 DVK this is simply done by connecting a USB cable. Open a command shell/terminal on Linux and enter sudo hciconfig. This will return the existing HCI devices. If the PC has an integrated Bluetooth/LE controller, this will be shown as hci0 device. For testing we shut down the integrated BT controller. (If there is no internal BT controller this step can be skipped.) Next step is attaching the IF820 module to the Linux HCI subsystem by setting the proper serial port, baud rate and other parameters. Another sudo hciconfig command should now display the new HCI device as hci1. Now the new Bluetooth/LE HCI device is ready to be used by an application. For testing we can use the command sudo hcitool -i hci1 lescan, which will scan for BLE advertisements from peripheral device in range.