MC144144

1

MOTOROLA

Advance Information

Enhanced Closed-Caption

Decoder

CMOS

The MC144144 is a Line 21 closed–caption decoder for use in television

receivers or set–top decoders conforming to the NTSC standard. Capability for

processing and displaying all of the latest standard Line 21 closed–caption

format transmissions is included. The device requires a closed–caption

encoded composite video signal, a horizontal sync signal, and an external

keyer to produce captioned video. RGB and box signal outputs are provided,

which along with the mode select, allow simple interfacing to either color or

black–and–white TV receivers.

Display storage is accomplished with an on–chip RAM. A modified ASCII

character set, which includes several non–English characters, is decoded by an

on–chip ROM. An on–screen character appears as a white or colored dot matrix

on a black background.

Captions (video–related information) can be up to four rows appearing

anywhere on the screen and can be displayed in two modes: roll–up, paint–on,

or pop–on. With rollup captions, the row scrolls up and new information appears

at the bottom row each time a carriage return is received. Pop–on captions work

with two memories. One memory is displayed while the other is used to

accumulate new data. A special command causes the information to be

exchanged in the two memories, thus causing the entire caption to appear at

once.

When text (non–video related information) is displayed, the rows contain a

maximum of 32 characters over a black box which overwrites the screen.

Fifteen rows of characters are displayed in the text mode.

An on–chip processor controls the manipulation of data for storage and

display. Also controlled are the loading, addressing, and clearing of the display

RAM. The processor transfers the data received to the RAM during scan lines

21 through 42. The operation of the display RAM, character ROM, and output

logic circuits are controlled during scan lines 43 through 237. The functions of

the MC144144 are controlled via a serial port which may be configured to be

either I2C or SPI.

• Conforms to FCC Report and Order as Amended by the Petition for

Reconsideration on Gen. Doc. 91–1

• Conforms to EIA–608 for XDS Data Structure

• Supports Four Different Data Channels for Field 1 and Five Different Data

Channels for Field 2, Time Multiplexed within the Line 21 Data Stream:

Captions Utilizing Languages 1 and 2, Text Utilizing Languages 1 and 2

and XDS Support

• Output Logic Provides Hardware Underline Control and Italics Slant Generation

• Single Supply, Operating Voltage Range: 4.75 to 5.25 V

• Supply Current: 20 mA (Preliminary)

• Operating Temperature Range: 0 to 70°C

• Composite Video Input Range: 0.7 to 1.4 V p–p

• Horizontal Input Polarity: Either Positive or Negative

• Internal Timing and Sync Signals Derived from On–Chip VCO

In this document, the term ‘user’ refers to the television or VCR designer. The user may choose to make certain optional features selectable by

the viewer. These features then become viewer options.

This document contains information on a new product. Specifications and information herein are subject to change without notice.

Order this document

by MC144144/D

MOTOROLA

SEMICONDUCTOR TECHNICAL DATA

MC144144

P SUFFIX

PLASTIC DIP

CASE 707

ORDERING INFORMATION

18

1

MC144144P

Plastic DIP

PIN ASSIGNMENT

HIN

BLUE

GREEN

VSS

LPF

CSYNC

VIDEO

SMS

SEN

SCK

SDO

BOX

RED

RREF

VSS(A)

VDD

VIN/INTRO

SDA

14

15

16

17

18

10

11

12

13

5

4

3

2

1

9

8

7

6

REV 1

11/95