Overview

Ideal for printers, scanners, tape drives, set-top boxes, and data acquisition applications, the CD1284 is a multi-function interface controller that implements a high-speed, multi-protocol parallel port and two asynchronous serial ports. The device has both programmed I/O and DMA operation (parallel port only), providing flexibility in local CPU interface design and high-speed data transfers between the device and main memory.

Product Features

Parallel Port (Peripheral-side)

High-speed, bidirectional, multi-protocol parallel port:

■ Hardware implementation of all modes of the IEEE STD (Standard) 1284 specification (including automatic negotiation)

—Centronics® -compatible mode

—Reverse Byte mode

—Reverse Nibble mode

—ECP (extended capabilities port) mode with run-length encoding/decoding

—EPP (enhanced parallel port) mode

—Up to 2-Mbytes/sec. transfer rate in ECP and EPP modes

■ 64-byte parallel FIFO with DMA interface

Two Serial UARTs

■ Serial channel asynchronous protocol support to 115.2 kbps (register-setcompatible and functionally identical to CD1400)

—Twelve-byte FIFOs for each transmitter and receiver with programmable threshold for receive FIFO interrupt generation

—Improved interrupt schemes: Good Data™ interrupts eliminate the need for character status check

—User-programmable and automatic flow control for serial channels

—Special character recognition and generation.

—Special character processing, particularly useful for UNIX® environments, optionally handled automatically by the serial channels.

—Six modem control signals per channel (DTR, DSR, RTS, CTS, CD, and RI)