DESCRIPTION

The Philips Semiconductors SCN26562 Dual Universal Serial Communications Controller (DUSCC) is a single-chip MOS-LSI communications device that provides two independent, multi-protocol, full-duplex receiver/transmitter channels in a single package. It supports bit-oriented and character-oriented (byte count and byte control) synchronous data link controls as well as asynchronous protocols. The SCN26562 interfaces to synchronous bus MPUs and is capable of program-polled, interrupt driven, block-move or DMA data transfers.

FEATURES

General Features

• Dual full-duplex synchronous/asynchronous receiver and transmitter

• Multiprotocol operation

– BOP: HDLC/ADCCP, SDLC, SDLC loop, X.25 or X.75 link level, etc.

– COP: BISYNC, DDCMP

– ASYNC: 5–8 bits plus optional parity

• Four character receiver and transmitter FIFOs

• 0 to 4Mbit/sec data rate

• Programmable bit rate for each receiver and transmitter selectable from:

– 16 fixed rates: 50 to 38.4k baud

– One user-defined rate derived from programmable counter/timer

– External 1X or 16X clock

– Digital phase-locked loop

• Parity and FCS (frame check sequence LRC or CRC) generation and checking

• Programmable data encoding/decoding: NRZ, NRZI, FM0, FM1, Manchester

• Programmable channel mode: full- and half-duplex, auto-echo, or local loopback

• Programmable data transfer mode: polled, interrupt, DMA, wait

• DMA interface

– Single- or dual-address dual transfers

– Half- or full-duplex operation

– Automatic frame termination on counter/timer terminal count or DMA EOPN input

• Interrupt capabilities

– Vector output (fixed or modified by status)

– Programmable internal priorities

– Maskable interrupt conditions

• Multi-function programmable 16-bit counter/timer

– Bit rate generator

– Event counter

– Count received or transmitted characters

– Delay generator

– Automatic bit length measurement

• Modem controls

– RTS, CTS, DCD, and up to four general purpose pins per channel

– CTS and DCD programmable auto-enables for Tx and Rx

– Programmable interrupt on change of CTS or DCD

• On-chip oscillator for crystal

• TTL compatible

• Single +5V power supply