This slide illustrates what a Bluetooth® system looks like from a hardware and software perspective. On the upper right-hand side, in red, is a Bluetooth transceiver device, for example the TI CC2560. The dotted line represents a Bluetooth module, which may include additional RF components. The transceiver will pair up with a host controller, either a microcontroller or a microprocessor, shown in gray, via a UART connection. The reason a microcontroller or processor is required, is shown on the software portion of the diagram. A number of software components are required in a wireless system, and thus require a controller or processor to run them, like an operating system, a stack, profiles, and applications. The Bluetooth device itself will also host some software, but typically only the firmware and low level protocols. As shown in the software diagram the host controller and Bluetooth transceiver communicate via a Host/Controller Interface.