JPS59176866A - Automatic wiring method of printed board - Google Patents

Abstract

PURPOSE:To decrease greatly the retrieving time for a multi-folded point pattern in a segment retrieving system for automatic wiring of a printed board, by storing the wiring enable information in the form of the segment end point data. CONSTITUTION:When two points A and B on a wiring mesh are connected to each other, a wiring enable segment is first detected among vertical and horizontal segments which pass through pins A and B. It is regarded that the connection is possible if the vertical (horizontal) line of A crosses the horizontal (vertical) line of B. Then the wiring data is stored in a mesh region. When those lines have no crossing, the attention is paid to the wiring enable segments l1 and l2 passing through points A and B in the same direction as shown in the figure. At the same time, the overlap area of both segments is also considered to check whether a vertical line exists within this E region. Thus nine regions are obtained as connection enable regions. The wiring enable segments thus obtained are stored in horizontal and vertical data buffers respectively, and at the same time a pattern is stored in the mesh region.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic wiring method for a printed circuit board, and more particularly to an automatic wiring method for a printed circuit board that uses a line segment search method to significantly reduce the search time for a multi-fold pattern.

The line segment search method is widely used when automatically wiring printed circuit boards using a computer program.

The line segment operation method means that when two points to be connected are given, horizontal and vertical search lines are drawn that pass through these points, and if these lines intersect in a way that connects the two points, the line is connected. These lines are considered to be successful and are used as a wiring pattern.

According to this method, especially when there are two wiring layers, it is possible to achieve much higher wiring density than by drawing mainly horizontal patterns in one layer and mainly vertical patterns in other layers. becomes. However, according to the conventional method, when the pattern is simple as shown in Figure 1, it is possible to connect at high speed, but it takes time to connect as shown in Figure 2. Are known. Figures 1 and 2
In the figure, ■ and W indicate two points to be connected, the vertical solid line is the front pattern, the horizontal broken line is the back pattern, the X mark is the through hole that connects the front pattern and the back pattern, and the diagonally shaded area is where wiring is prohibited. The areas are shown (the same applies hereafter).

In other words, considering the bending point as one degree of freedom, from point A to BAK
When finding a route that can be reached using vertical and horizontal lines, if you add up the number of attempts to find a possible route at each turning point, the number becomes enormous. In order to avoid a long search, a method has been considered to limit the number of bend points to a decimal number (for example, up to 4 points), but because of this, the route must be given up midway even though the route K is possible. This also caused some inconvenience.

The present invention has been made in view of these points, and
In the line segment search method, in order to minimize the search for mesh data for automatic wiring, possible wiring information is stored as line segment end point data, thereby greatly reducing the search time for multi-digit point patterns. This is a wiring method realized.

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 3 is a diagram showing the configuration of a system for implementing the present invention. In the figure, 1 is a CPU in which a wiring program is stored, 2 is a main memory with a wiring mesh data area 21. A horizontal line segment data buffer 22 stores one page of horizontal line segment data, and a vertical line data buffer 23 stores one page of vertical line segment data.
It's made up of a lot of things. Horizontal line segment data and vertical line segment data for two or more pages are stored in the external auxiliary storage device 3. FIG. 4 is a diagram showing an example of data stored in the wiring mesh data area 21. In the apparatus configured as described above, an automatic wiring program executed by the CPU 1 performs automatic wiring using the wiring mesh data and the horizontal and vertical line segment data in the memory 2.

The wiring mesh data represents the state of the minimum unit area when the two layers of the printed circuit board are divided into meshes at intervals of a certain wiring grid value (for example, 1.27 plates), and the wiring mesh area 21 is This shows the area where mesh data like this is stored. The state of the mesh data is ■
There are terminals, ■Wiring, ■Through holes, ``■Wiring prohibited, ■Through holes prohibited, ■Blank (wireable), etc.In reality, the status is written to the bits in the memory word as shown in the table in Figure 5. The routable line segment data stored in the data buffer 22 and 23 refers to the data when consecutive meshes with a routable status in the horizontal or vertical direction are connected in the wiring mesh data. A collection of lines to be found.A line is defined by the corrected coordinates of both ends.

If there are many lines in the data buffers 22 and 23,
Assuming that the data cannot be stored in the memory, all the data is stored in the auxiliary storage device 3 such as a magnetic disk, and only a part of the data (one page) is stored. As shown in the table of FIG. 6, one page has a length of 128 words and is provided for each ib line segment level.

For the line segment level, when looking from the starting point terminal ■ to the end point terminal ■, assign positive serial numbers to the horizontal and vertical wiring paths that approach ■, and negative serial numbers to the horizontal and vertical wiring paths that move away from ■. . Even if line segments on the same level are segmented traps, they are stored on the same page. At a certain point in time, as a result of examining a mesh to find a routeable line segment at a certain level, the line segment at that level is stored in the page. Line segments at the same level are not examined again in the mesh area 21.

FIG. 6 is a diagram showing the internal configuration of the horizontal and vertical data buffers 21 and 23 and the auxiliary storage device 3. A horizontal line segment data buffer 22 and a vertical line segment data buffer 23 exist in the main memory, and the auxiliary storage device stores an area where line segment data for each direction is stored, and line levels and line segment data addresses. It consists of an index area. When the line segment data address is -1, it means "the line does not exist", and when it is 0, it means "the line has not been found yet". The line segment coordinates are only the X coordinate when it is horizontal, and only the Y coordinate when it is vertical. The layer division is divided into layer A (component side) and layer B (soldering side), and it is possible to know whether the layer is horizontal or vertical depending on the layer.

Now, assume that two points A and B (hereinafter referred to as bins) are defined on two wiring meshes and a wire is connected between these two points. First of all,
As shown in FIG. 7, out of the vertical line segment (solid line) and the horizontal line segment (broken line) passing through pins A and B, a line segment that can be wired is found. Initially, horizontal and vertical line segment data buffer 2
Since 2.23 is cleared and there is no data, the mesh data area 21 is examined to find it. The horizontal and vertical line segment data obtained in this manner are stored in line segment data buffers 22 and 23, respectively. The wiring obtained in this way is called the primary wiring. Next, the vertical line of A (
If the horizontal line (horizontal line) and the horizontal line (vertical line) of B intersect, it is considered that connection is possible, and these lines are wired as shown in FIG.

The laid wiring data is stored in the mesh area 21VC. If they do not intersect, the CPU 1 determines that the pattern requires two or more through holes.

FIG. 9 is a diagram showing an example in which neither horizontal nor vertical lines passing through two points A and B intersect. For this example,
Pay attention to the routable line segments (horizontal lines in this case) t and t2vr in the same direction that pass through the two points A and B.

As for tl and 12, as shown in the figure, they are KB area overlapped parts. Next, one checks whether a vertical line exists within this overlap region. Vertical wiring area ■, ■...0
..., and when searching for a connectable area, the area shown in the figure is ■
It can be seen that it is possible to connect in the area.

This perpendicular line is connected to the horizontal line t1. by two through holes, respectively. Connected to smell. Wiring possible A obtained in this way
are horizontal and vertical line segment data: buffer 22.2
3K are stored, and a pattern is stored in the 1 mesh area 21-. In subsequent searches, if line segment data at the same location is required, the pattern state of the mesh area can be extracted again by one mesh, thereby greatly reducing the search time.

For example, even in a search where only the pattern shown in Fig. 10 can be found, horizontal direction ■~■ and vertical direction ■
By calculating the line segments in the horizontal and vertical wiring area of ~ [phase] once and storing each line segment in the data buffer 22.23K, from then on, connections within the overlapping state of the lines can be performed. It is possible to perform a high-speed search by simply repeatedly checking the existence of line segments to find complex patterns of wiring without having to check each mesh one by one.
Become.

As explained in detail above, according to the present invention, in order to suppress the search for mesh data for automatic wiring to a minimum of 1%, possible wiring information is stored together with line segment end point data, so that multi-fold pattern It is possible to realize an automatic wiring method for printed circuit boards that significantly reduces search time.

[Brief explanation of the drawing]

1 and 2 are diagrams showing a pattern connection method, FIG. 6 is a diagram showing the configuration of a system for implementing the present invention, and FIG. 4 is a diagram showing an example of patterns stored in the mesh area. , Figure 5 is a table showing the configuration of mesh data, Figure 6 is a diagram showing the configuration of data buffer 1 and auxiliary storage device, Figure 7 is a diagram showing line segments that can be wired, and Figures 8 to 10 are wiring diagrams. FIG. 2 is a diagram illustrating the method. 1...CPU, 2...Main memory, 3...Auxiliary storage device, 21...Ishigourd area, 22...Horizontal line segment data buffer 1.23...Vertical line segment data buffer. Fig. 6 - Main memory → <-11--11-1-- Gansuke reference circle □ Fig. 7

Claims (1)

[Claims] Automatic wiring method for a printed board (1) having the following steps:
Memory for storing printed board wiring data,
The printed board is divided into a mesh area by a wiring grid, and a line segment data area is allocated to store line segments that can be wired in the horizontal and vertical directions. (2) Focusing on the two points to be wired, find the horizontal and vertical line segments that pass between these two points. (3) Among the routeable line segments obtained in (2), if the horizontal line (vertical line) at one point intersects the vertical line (horizontal line) at the other point, it is assumed that the line can be connected and those lines are routed. However, the wiring data is stored in the mesh area. (If the horizontal line (vertical line) at one point and the vertical line (horizontal line) at the other point do not intersect among the routeable line segments determined in 41 (2), two or more through holes are required. It recognizes that the pattern is a pattern that connects two points, checks for overlapping routable line segments in the same direction that pass through the two points to be connected, and searches for connecting line segments between those line segments. Store possible line segments in the line segment data area by direction and level, and register the presence or absence of line segments in the index. (5) When checking the overlap of line segments and the existence of connected line segments in the future , the line segment index is referenced to determine whether a line segment that has already been found exists.