JPS59177643A - Controller for plotting speed of raster type plotter - Google Patents

Abstract

PURPOSE:To prevent the stop of a plotter to improve the picture quality by reading preliminarily data with a graphic processor, and controlling the read speed of data from a frame buffer to a plotter input/output part in accordance with the result of this read. CONSTITUTION:Data is taken in from a line E through a channel adapter 21 and is stored in a segment buffer 22. A graphic processor 23 checks data in the buffer 22 to obtain the number of vectors and the number of areas to be smeared in one band having a certain width and calculates the time required for data processings. Every one band of data is stored in two frame buffers 26 through a bit map controller BMC24 and a raster data converting part DDA25. Data is sent to a plotter 28 through a plotter interface part 27 in a plotting speed indicated by the graphic processor 23. Thus, data is read from and written in frame buffers 26 alternately and is plotted continuously by the plotter 28 to prevent the dirt due to blur of a developer and drop-out of data.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improving image quality by controlling the drawing speed of a raster plotter.

In general, with a raster plotter, if you stop plotting the plotter (i.e., stop printing the recording paper), the developer will seep into the paper and stain the drawing, and if you suddenly stop or start printing blocks. , the middle of the diagram is missing.

The outline of the conventional raster plotter system is as shown in Figure 1. In order to prevent the output of the p1 plotter from stopping in the middle of one section, two frame buffers are prepared.
While the data in one frame buffer is being output to the block-interface 12, the data in the other frame buffer is
The method used was to store data in a buffer while performing vector/raster conversion using the CPU 13. However, even with this method, if the drawing is complex and has a large number of vectors, the vector/raster conversion cannot keep up with the block printing speed, and the plotter has to stop printing eventually. .

The present invention was made in order to solve the above-mentioned drawbacks, and it reads vector data in advance, determines how crowded the data is, reduces the output speed of the plotter when the number of vectors is large, and performs vector/raster conversion. The purpose of this is to save time and prevent the plotter from stopping mid-way.

The present invention will be described in detail below with reference to the drawings.

FIG. 2 schematically shows a system for implementing the present invention.

This system consists of a channel adapter 21 that receives data from line E, a segment buffer 22 that stores the data, a graphics processor that sends out the stored data little by little, and fill-in processing for this data. A BMC (bit emap controller) 24 that performs
, a DDA (vector data converter) that converts the vector data output from this EMC24 into raster data.
25, two frame buffers 72G for storing this raster data, a plotter interface 27 for outputting the raster data in this buffer 26 to a plotter, and
It is comprised of a raster type plotter 4 that outputs drawings according to the output from this interface 27.

Guofiku is in charge of controlling the entire system.
The main program of the processor is stored here. In addition, BMC24 and DDA5 have micro
Programs are stored and data processing is performed by this micro V blog. Also, in the drawing B
1 to B5 are buses for transmitting data between the respective blocks.

Vector data created by a host computer (not shown) is stored in segment buffer 22 via line E and p-channel adapter 21. This vector data is divided into fixed widths in the X-axis direction by the host computer (the unit of division 9 is called a band).
If there is a figure that spans between bands, it is divided so that vectors do not continue between bands. In addition, l
The width of the band is constant for any drawing. In addition, it has a segment buffer of 22fd with a capacity of 1 megabyte, which has a capacity to store data for 100,000 vectors, and is large enough to accommodate data for one drawing, and can be expanded as necessary. is also possible.

The vector data stored in the segment buffer 22, including graphics, is divided into BMs one band at a time depending on the processor%.
The image is sent to the C24, where it is subjected to processing such as filling, and then sent to the DDA25. DDA 25 tri,
The vector data is converted into raster data and stored in one of the two frame buffers 26.

The data in the other frame buffer of R5 is output to the plotter interface 27 and drawn by the plotter 4.

Now, if it takes 10 seconds to output at the maximum speed to draw on all plot blocks of the frame meeting buffer 2G, then the K that processes the data without stopping the plotter is the processing in BMC24- and DDA5. must be completed within 70 seconds.

However, if fill-in processing is performed or if the number of vectors is large, the processing time may take 10 seconds or more.

FIG. 3 is a flowchart for explaining the drawing speed control function performed by the graphics processor.

Before starting the processing of one band, Graphic Ken Pro Nanatsusa n counts the number of vectors in the band and the number of ax crushing data, and calculates the time required for data processing. Since the execution speed of one micro program instruction is known, the processing time can be easily calculated if the number of instruction steps of the micro Φ program stored in the BMC 24 and DDA 25 is known.

TF: T-work
F-+-TV TF: Time required for fill-in T: Execution time of micro-program l instruction F: Number of micro-program steps for fill-in DF: Number of data for fill-in Tv: Vector raster Time required for conversion ■Number of steps in the micro program for conversion Dv: Number of vector data T Processing time for processing time If the calculated total processing time T seconds exceeds 70 seconds, the amount of time required for conversion from the graphics processor 23 to the plotter - Issue a command to the interface 27 to reduce the drawing speed of the plotter 4 by To/'rK to increase data processing time. This command is executed by BMC24, DDA25. The frame buffer 26 is connected to the bus B2. B3. B4
．． B5 to block interface 27.

Plotter 21j: 7” lock interface 27
Since it is operated by synchronizing pulses sent from the printer, the drawing speed of the printer can be controlled by changing the period of the pulses.

In this way, if the output to the plotter A is controlled at the speed of To/'I', when the data in one frame buffer 26 finishes outputting, the data in the other frame buffer 26 will be output.
Now that the data in the aforementioned band has been raster-converted and inputted, the recording paper can continue drawing without stopping.

As described above, according to the present invention, it is possible to control the plotter's drawing speed by pre-reading data with the graphics processor, so data can be processed without stopping blocks, and development There is no liquid seeping into the paper and staining it, there is no stopping of the plotter, there is no data dropout when starting up, and high-quality drawings can be obtained.

[Brief explanation of drawings]

FIG. 1 is a schematic block diagram of a conventional raster plotter.
FIG. 2 is a schematic block diagram of a system for implementing the present invention, and FIG. 8g3 is a flowchart for explaining the operation of the system VC shown in FIG. 21: Channel adapter 22: Segment buffer 23: Graphic processor 24: BMC (pit map controller) 25:
DDA (vector raster converter) 26: Frame-buffer 27: Plotter ink-face 28 Two or more plotters Applicant Dinis Software Co., Ltd. Daini Seiko Co., Ltd. Agent Patent Attorney Saturn Senior Affairs

Claims (1)

[Claims] a segment buffer into which vector data is pledged;
A bit map control for processing the vector data output from this segment O buffer via the graphics processor, and a vector raster control for converting the vector data output from this control into raster data. - a plurality of frame buffers for writing the output of the converter and a plotter interface for allowing the data in the frame buffers to be plotted on an external plotter; Calculate the time required for vector transformation from the amount of data,
A drawing speed control device for a raster type plotter, characterized in that the data output speed of the plotter interface is changed according to this time.