KR20000040763A - Printer system for reducing bottleneck of memory usage - Google Patents

Abstract

PURPOSE: A printer system for reducing bottleneck in using a memory is provided to reduce the bottleneck with an intervener controlling a memory and separately with a second memory storing image data. CONSTITUTION: A printer system for reducing bottleneck in using a memory comprises a main processor(100), a first memory(1100), a co-processor(200), a second memory(1300), a video controller(400), memory controllers(1000,1200) and interveners(800,900). The main processor(100) generates/outputs a printer command to generate corresponding image data when print data is inputted from a host. The first memory(1100) stores the printer command. The co-processor(200) generates the image data by executing the printer command read from the first memory(1100). The second memory(1300) stores the image data. The video controller(400) transmits the image data to an image creating unit. The memory controllers(1000,1200) control data access. The interveners(800,900) receive one memory respectively, and generate authentication signals according to a request to intervene the memory.

Description

Printer system and its method to reduce the memory bottleneck

TECHNICAL FIELD The present invention relates to a printer system, and more particularly, to a printer system and method for reducing bottlenecks of memory usage.

In order to obtain high-resolution print quality and develop a printer that operates at high speed, the processor and memory must be very fast. In particular, since memory is used not only in the processor but also in each input / output interface or co-processor during printer operation, high-speed printers require high-speed memory. However, you cannot use high-speed memory to implement a high-speed printer. The reason for this is that product prices rise by that much. Accordingly, there is a need for a method and apparatus for implementing a high speed printer using a memory having a general speed.

FIG. 1 shows some block diagrams of a typical printer system, showing only four major functional blocks that use the most memory 700 in the printer system. FIG. 2 is a timing diagram illustrating the mediation process of using the memory 700 shown in FIG. 1.

Referring to FIG. 1, the processor 100 represents a microprocessor and controls the overall operation of the printer system. The Graphic Execution Unit (GEU) 200 mainly processes a bitmap rendering function, which is a part of the processor 100, and is a coprocessor that assists the control function of the processor 100. The compression / extension unit 300 serves to compress / extend the bitmap generated by the GEU 200, and the PVC (Printer Video Controller) 400 synchronizes with the clock from the printer engine unit during a print operation. To transmit the bitmap data to the engine unit. The arbiter 500 arbitrates when the memory 700 is used from the various functional blocks described above, and the memory controller 600 controls the memory data access to the memory 700. Record or read predetermined data.

There is one memory included in the above-described general printer system, and there are four functional blocks using the provided memory. Accordingly, an arbiter 500 is required to arbitrate the right to use the memory, and the arbiter 500 grants the memory use according to priority when there is a memory use request. In FIG. 2, two functional blocks simultaneously request memory usage (REQ1, REQ2), but only one functional block receives an acknowledgment (ACK1) from the arbiter 500 according to a specified priority, and the memory 700 preferentially. After the use of the memory 500 is completed, another function block requesting the use of the memory receives an acknowledgment (ACK2) to use the memory 700.

Therefore, in a general printer system using several memory blocks simultaneously, a printing bottleneck is delayed according to frequent memory bottlenecks as described above.

Accordingly, an object of the present invention is to provide a printer system and a method capable of speeding up printing speed by reducing a bottleneck of memory usage.

The present invention for achieving the above object is a printer system for reducing the bottleneck of memory use,

A main processor for generating and outputting a printer command so that image data corresponding to the print data is generated from the host;

A first memory in which the generated printer commands are stored;

A co-processor (C0-Processor) for generating image data by executing a printer command read from the first memory;

A second memory in which the image data is stored;

A video controller which transmits the image data read from the second memory to an image forming unit;

Memory controllers connected to each of the memories to control data access;

Each of the one of the memories is assigned to generate an acknowledgment signal in accordance with the memory use request, characterized in that it is configured as an arbitrator to mediate the memory use.

1 is a block diagram of a part of a general printer system.

FIG. 2 is a timing diagram illustrating an arbitration process of using the memory 700 shown in FIG. 1.

Figure 3 is a block diagram of a printer system according to an embodiment of the present invention.

FIG. 4 is an exemplary timing diagram illustrating an arbitration process of using the memories 1100 and 1300 illustrated in FIG. 3.

Hereinafter, an operation according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.

3 is a block diagram of a printer system according to an exemplary embodiment of the present invention, and FIG. 4 is a timing diagram for explaining an arbitration process of using the memory 1100 and 1300 of FIG. 3, respectively. .

First, referring to FIG. 3, when the print data is input from a host such as a personal computer through a parallel port or a LAN, the processor 100 generates a printer command for generating image data corresponding to the main memory ( 1100). If the printer is a laser beam printer, the processor 100 divides one page of data into several bands and processes them in band units, and displays a display list of all bands of one page, that is, a bit map. A printer command that can be generated is generated to cause the GEU 200 to execute the generated commands. The processor 100 generates a display list for the next page while the co-processor GEU 200 executes the display list in band units. Therefore, the processor 100 and the GEU 200 may operate independently of each other because they work on different pages.

The co-processor GEU 200 generates bitmap data by reading and executing a printer command generated by the processor 100 and stored in the main memory 1100. Since the bitmap generated by the GEU 200 occupies a large area of memory, it is sometimes compressed into a small amount of data through a compressor, and then compressed in real time through a decompressor during printing. You can print by restoring the bitmap. Therefore, the bitmap data generated by the GEU 200 is compressed through the compression / extension unit 300 and then stored in the band memory 1300, and is read during printing and reconstructed through the compression / extension unit 300 again. The bitmap data is restored. The band memory 1300 is a memory having a considerably smaller capacity than the main memory 1100 and may be embedded in a chip during ASIC development.

Meanwhile, the PVC 400 reads data stored in the band memory 1300 through the compression / extension unit 300 and transmits the data according to a clock input from the image forming unit (or print engine unit). Arbitrator 1 800 arbitrates memory usage rights between processor 100 and GEU 200 that access main memory 1100. The arbiter 2 900 arbitrates memory usage rights between the GEU 200, the compression / extension 300, and the PVC 400 that access the band memory 1300. That is, the arbiter 1 800 and the arbiter 2 900 respectively use the memory use acknowledgment signal ACKn according to the arbitration result when the memory use request signal REQn is simultaneously input from the functional blocks that access the designated memory. Output sequentially to the requested function block. Each of the memory controllers 1000 and 1200 controls data access of the connected memory 1100 and 1300.

As described above, in a printer system including a band memory 1300 that stores bitmap data in addition to the main memory 1100, a bottleneck of memory usage may be reduced by the following arbitration process.

First, as shown in FIG. 4 in the processor 100 and the GEU 200, when the memory usage request signals REQ1 and REQ2 for using the main memory 1100 occur at the same time, the arbiter 1 800 is assigned to the designated priority. Accordingly, the memory usage approval signal ACK1 is generated and output to the processor 100. Accordingly, the processor 100 may access the main memory 1100 through the common bus. Meanwhile, when the memory 100 of the processor 100 is completed, the arbiter 1 800 enables the GEU 200 to use the main memory 1100 by activating the memory use approval signal ACK2.

In addition, when the processor 100 requests the use of the main memory 1100, the GEU 200 and the PVC 400 generate memory use request signals REQa and REQb for using the band memory 1300, respectively. The second 900 generates a memory use approval signal ACKa according to a specified priority, and outputs it to the GEU 200. Accordingly, the GEU 200 accesses the band memory 1300 through the common bus, and when the use of the band memory 1300 is completed, the arbiter 2 900 approves the use of the active memory to the waiting PVC 400. Output the signal ACKb. Accordingly, the PVC 400 accesses bit map data from the band memory 1300 and transmits the bit map data to the image forming unit.

Accordingly, the present invention can reduce bottlenecks when using the memory because the band memory 1300 for storing bitmap data and the arbiters for mediating each memory are provided in addition to the main memory 1100.

As described above, the present invention includes a second memory for storing image data in addition to the main memory, and an arbitrator for arbitrating each memory use, thereby significantly reducing bottlenecks when using the memory and printing. This has the advantage of speeding up.

Claims (2)

A printer system for reducing the bottleneck of memory usage, A main processor for generating and outputting a printer command so that image data corresponding to the print data is generated from the host; A first memory in which the generated printer commands are stored; A co-processor (C0-Processor) for generating image data by executing a printer command read from the first memory; A second memory in which the image data is stored; A video controller which transmits the image data read from the second memory to an image forming unit; Memory controllers connected to each of the memories to control data access; And arbiters for allocating one of the memories to generate an acknowledgment signal according to a memory use request and to arbitrate the memory use. In a method for reducing the bottleneck of memory usage in a printer system, Generating a printer command to generate image data corresponding to the print data input from a host, and storing the generated printer command and the image data in different memories, respectively; A second process of requiring the use of the memory to convert, compress, extend, and transmit printer commands and image data stored in each of the memories; Mediating memory usage when there are multiple memory usage requests for each of the memories; And a fourth step of sequentially approving each memory use according to the arbitration result.