This slide shows the block diagram of the XR16M890 device. This UART supports a user selectable 8-bit or VLIO interface and can also operate from 1.62V to 3.63V. The VCC voltage levels for the CPU bus interface, UART I/Os, GPIOs and the core can all be at the same or different levels within this range. Similar to the XR20M1280, the XR16M890 offers options for the number of GPIO pins available, different package sizes, and the on-chip fractional baud rate generator.