ST16C2552

•Pin-to-pin and functionally compatible to National
PC16552 and Exar's XR16L2752 and XR16C2852
•4 Mbps transmit/receive operation (64 MHz
External Clock Frequency)
•2 Independent UART Channels
•DMA operation and DMA monitoring via TXRDY#
and RXRDY# pins
•UART internal register sections A & B may be
written to concurrently
•Multi-Function output allows more package
functions with few I/O pins
•Programmable character lengths (5, 6, 7, 8) with

even, odd, or no parity
•Crystal oscillator or external clock input

The ST16C2552 (2552) is a dual universal asynchronous receiver and transmitter (UART). The ST16C2552 is an improved version of the PC16552 UART. The 2552 provides enhanced UART functions with 16 byte FIFOs, 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. Indepedendent programmable baud rate generators are privded 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 loop-back capability allows onboard diagnostics. The ST16C2552 provides block mode data transfers (DMA) through FIFO controls. DMA transfer monitoring is provided through the signals TXRDY# and RXRDY#. AnAlternate Function Register provides the user with the ability to initialize both UARTs concurrently. The ST16C2552 is available in the 44-PLCC package.