The XR16C2550 (2550) is a dual universal asynchronous receiver and transmitter (UART). The XR16C2550 is an improved version of the PC16550 UART with higher operating speed and faster access times. The 2550 provides enhanced UART functions with 16 byte FIFO's, a modem control interface, and data rates up to 4 Mbps. Onboard status registers provide the user with error indications and operational status. System interrupts and modem control features may be tailored by external software to meet specific user requirements. Independent programmable baud rate generators are provided to select transmit and receive clock rates from 50 bps to 4 Mbps. The Baud Rate Generator can be configured for either crystal or external clock input. An internal loopback capability allows onboard diagnostics. The 2550 is available in a 44-pin PLCC and 48-pin TQFP packages. The 2550 is fabricated in an advanced CMOS process capable of operating from 2.97 volt to 5.5 volt power supply.