Overview

The LC82151 is a facsimile controller that integrates the main functions required by facsimile systems on a single chip. The LC82151 includes a FAX modem with ADPCM and HDLC functions, image processing functions that can create high-quality binary image data without external memory, a CODEC accelerator, a CPU and CPU peripheral circuits, general-purpose I/O ports, and other functions. A facsimile system with excellent cost performance characteristics can be created easily by providing ROM and RAM.

Functions

• CPU and peripheral circuits

– High-speed 16-bit CPU (65C816) operating at 7.4 MHz

– 16-MB program address space

– CODEC accelerator

– Two-channel DMA controller

– Four 16-bit timers

– 16-bit watchdog timer

– TPH interface

– Serial I/O interface

– Parallel I/O: 10 to 43 pins

• Image processing

– Processes 2048 pixels per line

– Processing speed: 540 ns per pixel (maximum)

– Built-in 8-bit A/D converter (Includes a sensor signal delay function.)

– Sensor drive circuit (Supports CCDs and all major CIS devices.)

– Distortion correction (White distortion: 8-pixel averaging correction, black correction: Allows the black correction subtraction data to be set.)

– γ-correction (Supports user-defined correction curves.)

– Simple binary conversion processing (fixed threshold and density-adaptive threshold)

– Halftone processing error diffusion method (64 levels)

– Image reduction (decimation, fine black line retention, and fine white line retention)

• Modem

– Group 3 FAX modem

ITU-T V.29 (9600, 7200, and 4800 bps)

ITU-T V.27ter (4800 and 2400 bps)

ITU-T V.21ch2 (300 bps)

– Simultaneous high/low-speed wait function

– Short training function (ITU-T V.27ter only)

– HDLC function (for all transmission speeds)

– Synthesizer function

– Caller ID function

Bell 202 (1200 bps)

ITU-T V.23 (1200 bps)

– ADPCM function

Encoding: 2, 3, or 4 bits

Sampling frequencies: 9.6, 7.2, 4.8, and 3.6 kHz

– RTC low-voltage backup

– 5-V single-voltage power supply