Apparatus and method for peripheral device control with integrated data compression

• US 5,721,958 A
• Filed: 12/04/1996
• Issued: 02/24/1998
• Est. Priority Date: 04/11/1995
• Status: Expired due to Fees

• Current Assignee: PDACO LIMITED
• Original Assignee: Elonex IP Holdings Limited
• Inventors: Kikinis, Dan
• Primary Examiner(s): SHAH, ALPESH
• Application Number:
  US08/759,186
• Time in Patent Office: 447 Days
• Field of Search: 395/800.01, 395/888, 395/200.76, 395/200.77, 395/827, 395/828, 395/835, 395/882, 395/884, 395/891, 395/100, 395/103, 395/101, 395/110, 395/523, 382/232, 382/233, 382/235, 382/254
• US Class Current: 345/555
• CPC Class Codes: G06F 3/12 Digital output to print unit , e.g. line printer, chain printer
• CPC Class Codes: G06F 3/1297 Printer code translation, conversion, emulation, compression; Configuration of printer parameters
• CPC Class Codes: G06K 15/00 Arrangements for producing a permanent visual presentation of the output data , e.g. computer output printersprinting or plotting combined with another operation, e.g. with conveying, G06K17/00
• CPC Class Codes: G06K 2215/0011 characterised by a particular command or data flow, e.g. Page Description Language, configuration commands
• CPC Class Codes: G06K 2215/0014 Transforming the printer input data into internal codes

Abstract

An apparatus and methods are provided for pre-compressing data to be sent to a peripheral device in a computer system, sending the data to the peripheral device as a compressed data stream, and decompressing the data for use in the peripheral device in a real-time format. In a preferred embodiment, a unique peripheral device controller is provided having a data handling and decompression pipeline for receiving and decompressing an incoming compressed data stream in concert with a state machine for sensing the states of elements of the peripheral device, and for providing the decompressed data stream to data-using elements of the peripheral device. The peripheral device can be any device for which large amounts of data are typically needed, including, but not limited to printers, video displays, robotic driving devices, and data recording and media writing devices. Alternative methods are disclosed for compressing and decompressing data in systems according to the invention.

Claims

1. A computer, comprising:

a CPU;

a memory;

a video adapter having a video controller, a compression engine, video random-access memory (VRAM), and a data interface to a video display, all connected by a video bus;

a bus system connecting the CPU, the memory, and the video adapter; and

control routines executable by the video controller for processing and sending data to the data interface;

wherein the video controller, executing the control routines, compresses data using the data compression engine, stores the compressed data in the VRAM, and retrieves and sends the compressed data to the data interface.

2. A computer as in claim 1 wherein the data interface is a Video Graphics Array (VGA)-compatible data interface.

3. A video adapter, comprising:

a video controller;

a video random access memory (VRAM);

a compression engine;

a data interface to a video display;

a local bus connecting the video controller, the VRAM, the compression engine, and the data interface; and

control routines executable by the video controller for handling data and sending the data to the data interface for transfer to the video display;

wherein the video controller, executing the control routines, compresses data using the data compression engine, stores the compressed data in the VRAM, and retrieves and sends the compressed data to the data interface for transfer to the video display.

4. A video adapter as in claim 3 wherein the video adapter is compatible with Video Graphics Adapter (VGA) standards.

5. A video adapter as in claim 3 wherein the adapter is an add-in expansion card adaptable to an expansion port of a computer expansion bus.