JPS6244953B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sewing pattern forming device for a sewing machine, and particularly to an improvement in a monitor display section during pattern formation.

In industrial automatic sewing machines, etc., sewing is performed repeatedly along a desired sewing pattern many times, and the sewing pattern is stored in a pattern memory such as P-ROM in order to arbitrarily change this sewing pattern to a desired shape. When sewing, the sewing pattern in this memory is read out and the desired shape is efficiently sewn multiple times, and when the sewing pattern is changed, the contents of this P-ROM are changed according to the desired shape. There is. Such a sewing pattern generator is operated by drawing a desired sewing pattern on an input board and electronically writing it into a memory.

When inputting the sewing pattern, the input data is displayed on a monitor in order to form an accurate pattern, and for this purpose the display CRT displays stitches along the input pattern.

A raster scan type CRT is usually used as the monitor display unit, but the time required to display one image is relatively long with this raster scan type CRT, and as a result, it may not be possible to secure the number of screens per second, resulting in flickering. In particular, there has been a problem in that it is not possible to obtain images of good quality for sewing patterns that include a large number of stitches exceeding 4,000 stitches, as has been the case in recent years.

Furthermore, according to the conventional raster scan CRT, for example, video RAM is used as a peripheral circuit of the CRT.
There was a problem in that the circuit configuration was complicated.

It is known that a random scan type CRT is used as a monitor display in order to improve various problems in the monitor display. According to this random scan CRT, stitches can be displayed with high resolution, and peripheral circuits can be This has the advantage of being flicker-free and ensuring the number of screens per second even for large amounts of data.

However, this random scan method
With a CRT, if the image information is stored in the entire storage area of the display memory, there will be no problem, but
If display information is stored in only a portion of this total capacity, for example, RAM, the scan data in the remaining free space is normally "0", so when this free space is transferred, the CRT screen One point: In the normal case, the beam was concentrated at one point in the center, which caused the problem of burning out the CRT screen.

The present invention was made in view of the above-mentioned conventional problems, and its purpose is to solve the problem by random scan.
An object of the present invention is to provide an improved sewing pattern forming device for a sewing machine that can prevent burning of a CRT screen in an information free area of the CRT.

To achieve the above object, the present invention provides a sewing pattern generator for a sewing machine that writes an arbitrary sewing pattern from an input board into a pattern memory and sequentially monitors and displays the input data on a random scan CRT. It has a display memory that temporarily stores input data, and the display memory is provided with an anti-burning bit for the empty area of the input data, thereby reducing the brightness of the CRT in the empty area to prevent burnout. It is characterized by

Preferred embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows a pattern former according to the present invention, and FIG. 2 shows its internal circuit.
A tablet digitizer 10 forming an input board is provided at the front of the device, and a stylus pen 12 is provided.
By drawing the desired sewing pattern on the tablet, this is converted into an XY image signal.
Under the control of the CPU 14, the P-ROM writing circuit 16
P- to form a predetermined pattern memory through
It is written to the ROM as a sewing pattern signal. The P-ROM is installed in a P-ROM socket 18 provided on the rear surface of the digitizer 10. Various modes and other information at the time of this input are displayed on the LED display board 20. CPU14 mentioned above
converts the input data from the digitizer 10 to P-
The program for writing to the ROM is written in the system program ROM 22, and the CPU 14 performs processing according to this program.Input data from the digitizer 10 is temporarily stored in the data memory 24 consisting of RAM, In the embodiment, the values are stored as relative value data indicating the XY coordinate data of the digitizer 10 by the amount of XY change of each stitch.

The input data of the digitizer 10 is stored in P-ROM.
A monitor display CRT26 is provided to monitor data when writing to the
Desired sewing patterns can be sequentially input from the digitizer 10 while viewing the monitor image on the CRT 26. In the present invention, a random scan type CRT is used as the CRT26,
Compared to normal raster scan type CRTs, it displays images with higher resolution and accurately displays even fine seams, and can simplify peripheral circuits such as video RAM, reducing the price of monitor equipment. can. A CRT controller 28 is provided to drive the CRT 26.
8 is supplied with control signals corresponding to the X and Y coordinates of the monitor image from an X data D/A converter 30 and a Y data D/A converter 32, respectively, and a brightness control signal from a brightness control circuit 34. There is.

In this embodiment, the monitor display of the sewing pattern by the monitor display CRT 26 is performed by the P-ROM.
The display memory 36 is a RAM that stores input data from the digitizer 10 as absolute value data of XY coordinates.
Consists of. The output of this display memory 36 is connected to two latches 38 and 4 for each X data and Y data.
Converter 30, 32 via 0 and 42, 44
The brightness information is also supplied to the brightness control circuit 34, thereby controlling the CRT controller 28.
can make the CRT 26 draw a monitor image that is faithful to the input data.

In this embodiment, the random scan
In order to display images on CRT26 at high speed,
It is characterized in that data transfer from the display memory 36 to the CRT 26 is performed by a direct memory access method using a DMA controller separate from the CPU 14 that controls writing to the P-ROM, thereby improving image quality and preventing flickering and other problems. It is possible to do so. In the embodiment, display memory 36 is controlled by CPU 14 when writing input data from digitizer 10 and when transferring this written data to CRT 26.
The display memory 36 is controlled by the DMA controller 46, and for this purpose, the display memory 36 is commonly connected to the CPU 14 and the DMA controller 46. However, in order to make the control by both controllers independent, a separation gate 48 is connected to the common bus. It is provided.

A characteristic feature of the present invention is that a burn-in prevention bit is provided in each stitch display signal of the absolute value RAM used as the display memory 36. , the brightness is controlled to be lowered by the anti-burning bit.

The sewing pattern forming device according to this embodiment has the above-mentioned configuration, and the operation of writing input data from the digitizer 10 into the P-ROM will be briefly explained below.

When the operator draws a desired sewing pattern on the surface of the digitizer 10 with the stylus pen 12, the digitizer 10 captures this sewing pattern as an electrical signal on the XY coordinates, which is sent to the CPU 14.
is written into the data memory 24 as relative value data for each stitch. The CPU 14 reads the relative value data written in the data memory 24 based on the program in the program ROM 22.
The sewing pattern is supplied to the ROM writing circuit 16, whereby a desired sewing pattern can be written into the P-ROM.

At the same time as writing the P-ROM, in this embodiment, input data from the digitizer 10 is sequentially written.
Image can be monitored by CRT26,
This image monitor uses the data memory 2 for monitoring.
A display memory 36 provided separately from the display memory 36 and a random scan type CRT 26 are used, and data transfer of the display memory 36 is performed by a DMA controller 46 independently of the CPU 14 for P-ROM writing. This makes it possible to form a display image at high speed and display extremely accurate seams.

FIG. 3 shows the bit configuration of the absolute value RAM, in which absolute value data is stored using 1 to 4 bytes, and in the figure, X ₀ to X ₁₅ indicate the absolute value of the X data; Y ₀ to _{Y 13} indicate the absolute value of Y data. _A0 to _A1 are luminance signals, and these _A0 to _A1 bits are used as anti-burning bits in the free area using this luminance signal, and in the embodiment, these bits are set to "00". Sometimes CRT26
You can reduce the brightness value of the screen to prevent screen burn-in.

As described above, according to the present invention, it is possible to perform good monitor display using a random scan CRT regardless of the size of stitch data.

[Brief explanation of the drawing]

FIG. 1 is an external view of a sewing pattern forming device to which the present invention is applied, FIG. 2 is a circuit diagram of the main part of the present invention, and FIG.
The figure is a bit configuration diagram of the absolute value RAM, and the same parts in each figure are given the same reference numerals. 10 is the tablet digitizer, 14 is the CPU, 24 is the data memory, 26 is the monitor display CRT, and 36 is the display memory. , 46 is a DMA controller, and 48 is an isolation gate.

Claims (1)

[Claims] 1 A sewing pattern generator for a sewing machine that writes an arbitrary sewing pattern from an input board into a pattern memory and sequentially monitors and displays the input data on a CRT using a random scan method, and has a display memory that temporarily stores the input data. , the display memory provides a burn-in prevention bit for the free area of the input data, and thereby the free area is
A sewing pattern forming device for sewing machines that reduces the brightness of the CRT to prevent burnout.