General description

The SC68C2550B is a two channel Universal Asynchronous Receiver and Transmitter (UART) used for serial data communications. Its principal function is to convert parallel data into serial data and vice versa. The UART can handle serial data rates up to 5 Mbit/s.

Features

■ 2 channel UART with 68 mode (Motorola) µP interface

■ 5 V, 3.3 V and 2.5 V operation

■ 5 V tolerant on input only pins1

■ Industrial temperature range

■ Up to 5 Mbit/s data rate at 5 V and 3.3 V, and 3 Mbit/s at 2.5 V

■ 16-byte transmit FIFO to reduce the bandwidth requirement of the external CPU

■ 16-byte receive FIFO with error flags to reduce the bandwidth requirement of the external CPU

■ Independent transmit and receive UART control

■ Four selectable Receive FIFO interrupt trigger levels

■ Software selectable baud rate generator

■ Standard asynchronous error and framing bits (Start, Stop, and Parity Overrun Break)

■ Transmit, Receive, Line Status, and Data Set interrupts independently controlled

■ Fully programmable character formatting:

◆ 5, 6, 7, or 8-bit characters

◆ Even, odd, or no-parity formats

◆ 1, 11⁄2, or 2-stop bit

◆ Baud generation (DC to 5 Mbit/s)

■ False start-bit detection

■ Complete status reporting capabilities

■ 3-state output TTL drive capabilities for bidirectional data bus and control bus

■ Line break generation and detection

■ Internal diagnostic capabilities:

◆ Loopback controls for communications link fault isolation

■ Prioritized interrupt system controls

■ Modem control functions (CTS, RTS, DSR, DTR, RI, CD)