JP2827271B2 - Printed board CAD device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a printed circuit board CAD apparatus in which undetermined wiring is specially displayed.

<Prior Art> The printed circuit board CAD device discussed in this specification is a CAD device that manually determines a wiring pattern. In addition, the printed circuit board and the mounting holes of the electronic components mounted on it are displayed on the CAT, and the wiring work is performed while pointing the coordinate points on the CRT one after another with a cursor, and the printed circuit board wiring data is stored. Create on top. The apparatus can automatically output a pattern drawing and the like for actually manufacturing a printed board based on the created wiring data.

An operator performs wiring routing work by operating a cursor while interacting with a computer via a CRT screen. In this wiring work, usually, addition, correction, and deletion of wiring patterns are performed in net units according to a net list.

A net is a group of component pins that should be connected at the same potential. The netlist is a list indicating which component pins are connected to each other, and is data input to the CAD device via a keyboard or the like at a stage before the wiring work.

When wiring work of a printed circuit board with electronic circuits built in at high density is advanced, at some point the wiring pattern of another net already wired becomes an obstacle and the connection work of unconnected nets can not proceed first Occurs. In such a case,
Temporarily suspend (say, hold) the routing operation of the working net, correct the routing route of the faulty net, and resume the routing work of the held net after removing the fault. I have to.

<Problems to be Solved by the Invention> However, in the above-described conventional printed board CAD apparatus, only one net can be held at a time, and the end points that can be in the hold state are the currently wired end point and the end point. (Target) only between two points. Then, after the pattern correction for removing the fault is performed, the wiring operation of the net in the hold state is restarted.

In other words, the conventional CAD device must determine the route in order from the net on which the wiring work was performed. In other words, the wiring of a net having a path failure in the middle is postponed, and the wiring work of another net is difficult to proceed one after another.

On the other hand, the wiring patterns are preferably equally distributed over the entire printed board, and in certain areas the wiring is dense,
In other areas, a printed board having a sparse pattern is not preferable. This is because bridges, signal leaks, and the like occur in an area where wiring is crowded.

For this reason, when performing printed circuit board wiring, it is reasonable to first determine the main wiring pattern so that the wiring patterns are uniformly distributed, and then determine the branch and leaf wiring patterns. However, the conventional CAD apparatus is not suitable for the design work for obtaining the above-mentioned uniform wiring density because only one net can be held.

SUMMARY OF THE INVENTION An object of the present invention is to provide a printed board CAD apparatus capable of displaying a wiring pattern that violates a design rule due to a failure in the middle as temporary wiring and displaying a large number of such temporary wiring.

<Means for Solving the Problems> The present invention provides a cursor operating device (1) for moving a cursor to an arbitrary position on a CRT, a function for reading a cursor coordinate value (21), and Switching means (2) for switching between actual wiring and temporary wiring; introducing the switching means and the output signal of the function (21);
A wiring pattern creation unit (22) for outputting coordinate values of a start point and an end point of an actual wiring connecting two points designated by the cursor, a signal indicating a display color of the actual wiring, and a flag signal indicating that the wiring is an actual wiring; It has a design rule that stipulates prohibition rules for printed circuit board wiring, compares the actual wiring already stored in the graphic data list (32) to be described later with the actual wiring output from the wiring pattern creation unit, If the design rule is not violated, a design rule check unit that writes the output data of the wiring pattern creation unit into a graphic data list to be described later, a switching unit and an output signal of the function (21) are introduced, and designated by a cursor. A hold pattern creating unit (24) that outputs the coordinate values of the start and end points of the provisional wiring connecting the two points, a signal indicating the display color of the provisional wiring, and a flag signal indicating that the provisional wiring is used. A graphic data list for storing output data of the hold pattern generation unit and output data of the wiring pattern generation unit introduced via the design rule check unit (32)
And means of:

<Operation> The embodiment that has passed the design rule check unit and the temporary wiring that has not passed the design rule check unit are stored in the graphic data list. Normally, temporary wiring is a wiring pattern that violates the rules that cannot be passed through, but this is displayed on the CRT in a color different from the actual wiring. Therefore, after the general wiring is performed, the work of partially correcting the rule violation into the normal wiring can be performed by paying attention to the temporary wiring.

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

FIG. 1 is a view showing an embodiment of a printed board CAD apparatus according to the present invention, FIG. 2 is a view showing the concept of a net list formed in a storage unit, and FIG. 3 is a view showing an example of a printed board and a wiring pattern. FIG. 4 is a diagram showing the concept of a graphic data list, and FIG.
6A and 6B are diagrams for explaining the pattern level, and FIGS. 6 and 7 are diagrams for explaining the operation of the apparatus shown in FIG.

The device according to the present invention includes an input device 10 and a computer.
20, a storage unit 30, a CRT 40, and a plotter block (not shown). The computer 20 performs a characteristic operation based on various programs stored in the storage unit 30 or a memory (not shown). However, it is considered that the configuration of the computer 20 is more easily understood by showing it in a functional block. 20 is represented by 21 to 25 functional blocks.

In FIG. 1, an input unit 10 includes a tablet (cursor operating device) for moving a cursor to an arbitrary position on a CRT 40 and an input unit 1 including a keyboard for inputting numbers and characters.
And a changeover switch 2 for instructing the computer 20 whether the line segment to be inputted is real wiring or temporary wiring.

The computer 20 includes a coordinate value reading function unit 21, a wiring pattern creation unit 22, a design rule check unit 23, a hold pattern creation unit 24, and a wiring pattern display processing unit 25.

The coordinate value reading function unit 21 reads a cursor coordinate value by introducing a signal from the tablet 1. Tablet 1
The coordinate value reading function unit 21 can use a known technique.

The wiring pattern creating section 22 operates when the changeover switch 2 selects the actual wiring. That is, the changeover switch 2
And the output signal of the coordinate value reading / reading function 21 are introduced, the start and end point coordinate values of the actual wiring connecting the two points designated by the cursor, a signal indicating the display color of the actual wiring, and the actual wiring And a flag signal indicating the following. Further, the wiring pattern creation unit 22 can output a level signal indicating which drawing level the output data is to be stored in and a line width signal indicating the thickness of the actual wiring.

Add a description. As shown in FIG. 5, in a CAD device, a printed board is captured on a number of surfaces, and these surfaces are called levels. For example, the wiring pattern on the surface on which the component is mounted is level 2 and the wiring pattern on the solder surface is level 3, and each wiring pattern is assigned a level number and stored in a graphic data list described later. The coordinates (X1, Y1) at each level are common as shown in FIG. Here, it is possible to instruct the input device 10 to display the wiring pattern diagrams of the levels n and (n + 1). As a result, a diagram of the printed board surface on which the wiring patterns of level n and (n + 1) are superimposed is displayed on the CRT 40. When the input device 10 instructs that the line segment to be input is a wiring pattern of level n, the wiring pattern creation unit 22 receives the signal and outputs the level signal n with the coordinate values of the start point and end point of the input line segment. Is output to the graphic data list. Since the display color of the wiring pattern is preset for each level,
When a level is designated, the signal 22 can output a signal indicating a display color corresponding to the level. Wiring pattern creation unit
Since the switch 22 also introduces the signal of the changeover switch 2, it can output a flag (for example, "1") indicating that it is an actual wiring together with the coordinate value of the line segment. Since the input device 10 can also input a numerical value of the line width, the wiring pattern creating unit 22 can output a signal indicating the line width in response to the input.

The design rule check unit 23 has a design rule that defines a rule for prohibiting printed circuit board wiring. An example of such a prohibition rule will be described.

Wiring patterns of different nets on the same level cannot intersect.

The distance at which the wiring patterns of different nets on the same level can approach each other is Amm. The numerical value A is determined by various conditions such as an electronic circuit and a printed circuit board to be designed, and the A value is set in the design rule check unit 23 in advance.

The design rule checking unit 23 compares the actual wiring output from the wiring pattern creating unit 22 with the actual wiring already stored in the graphic data list 32 (this actual wiring is the same as the actual wiring to be written. (The actual wiring belonging to the level), and it can be determined whether the design rule is violated. This determination can be made easily.

That is, the wiring pattern (for example, a straight line) can be specified mathematically by knowing the coordinates of the start point and the end point. And 2
The distance between the straight lines or whether the two straight lines intersect can be easily mathematically determined, and a program for making this determination is also known.

The design rule check unit 23 is a wiring pattern creation unit
The actual wiring output from 22 is compared with all the straight lines stored in the graphic pattern list 32 belonging to the same level as the actual wiring, and the above determination is made. Then, the data of the actual wiring conforming to the design rule is written to a predetermined address of the graphic data list 32. Also, the actual wiring data that does not conform to the design rules does not perform this write operation and outputs an alarm signal SA.

The hold pattern creating unit 24 operates when the changeover switch 2 selects the temporary wiring. That is, the output signals of the changeover switch 2 and the coordinate value reading function 21 are introduced, and the start and end point coordinate values of the temporary wiring connecting the two points designated by the cursor, the signal indicating the display color of the temporary wiring, and the temporary And a flag signal indicating the wiring. Further, the hold pattern creating unit 24 can output a level signal for storing the output data and a line width signal indicating the thickness of the temporary wiring. The configuration of the hold pattern generation unit 24 is substantially the same as the configuration of the wiring pattern creation unit 22, and thus the description thereof is omitted. Note that the level at which the temporary wiring is stored is set in advance. In addition, the flag indicating the temporary wiring is “0” (if the actual wiring is “1”). The output data of the hold pattern creation unit 24 is added directly to the graphic data list 32 via the bus 52 without passing through the design rule check unit 23. It can be stored in list 32.

When the wiring pattern display processing unit 25 receives, for example, a signal indicating that a wiring pattern of level n and (n + 1) is to be displayed from the input device 10, the level n and (n) are obtained from the graphic data list 32.
All the wiring data of +1) are read out, and a printed board pattern diagram as shown in, for example, FIGS. 6 and 7 is displayed on the CRT 40 from the data. Since such a wiring pattern display processing unit 25 is already known and is not a main part of the present invention,
Detailed description is omitted in this specification. Although the wiring pattern display processing unit 25 is illustrated as a configuration included in the computer 20, the configuration may be independent of the computer 20.

The storage unit 30 stores various data as a database. Fig. 1 shows the hold pattern creation unit
The figure data list (32) storing the output data of 24 and the output data of the wiring pattern creation unit introduced via the design ruler unit, and the netlist 31 are illustrated.

The operation of the FIG. 1 apparatus configured as described above will be described.

First, the operator uses the keyboard 1 to input various data relating to a printed board to be designed into the computer 20. Connection data between electronic components is one of them
One. The connection data is input for each net. Please refer to FIG. 2 and FIG. For example, IC01 and IC02 are arranged on a printed board as shown in FIG.
When pin 10 is to be connected, the operator sets this connection as net N0001 as shown in FIG.
To enter. Similarly, as the net N0002, IC01-01 and IC02
Enter −05.

As described above, when the net data summarizing the group of the component pins to be connected at the same potential is input from the keyboard 1, the computer 20 stores the net data in the net list 31 of the storage unit 30 by a function not shown in FIG. For example, they are stored in net order. Next, the operator places a cursor at a desired position on the printed board and determines the position of each electronic component mounted on the printed board.

Next, a drawing level to be wired (for example, in the case of a component surface pattern, level 2... See FIG. 5) is applied from the input device 10 to the computer 20. At this time, since the wiring work has not been performed yet, the graphic displayed on the CRT 40 is simply the outline indicating the wiring area of the printed board and the pin positions of the mounted electronic components.

The operator selects the actual wiring with the changeover switch 2, operates the tablet 1 to place the cursor at a desired position on the printed board, and sets the coordinates of the starting point and the ending point of the wiring pattern via the coordinate value reading function unit 21. It is added to the wiring pattern creation unit 22. The wiring pattern creation unit 22 outputs the coordinate values of the start and end points of the actual wiring, the display color of the actual wiring, the flag signal “1”, the level signal 2, and the line width by the above-described operations. Since the wiring area is “empty” at the beginning of such manual wiring, wiring that violates the design rule does not usually occur. Therefore, the output of the wiring pattern creation unit 22 is output to the design rule check unit.
After passing through 23, it is stored in the graphic data list 32 as shown in FIG. Since the data of the graphic data list 32 is sequentially read by the wiring pattern display processing unit 25, when a wiring is input to the computer 20 by the cursor, the line segment is immediately displayed on the CRT 40.

The operator inputs new wiring patterns to the computer 20 one after another while observing the state of the input wiring, and each wiring line is stored in the graphic data list 32.

FIG. 4 is an enlarged drawing of this graphic data list. In FIG. 4, the net N0001 is the line L01, L0
2, L03. Here, the lines L01 and L02 are real wiring (the flag signal is "1"), while the line L03 is a temporary wiring (flag signal "0").

Next, the operation in the case of performing temporary wiring will be described. As described above, the operator can input the coordinates of the start point and the end point of the actual wiring with the cursor, and can draw the lines so that the density of the wiring patterns on the printed board becomes uniform, for example. It is assumed that the wiring density gradually increases in this way, and the state shown by the solid line in FIG. 6 is reached. In FIG. 6, P01 to P20 represent terminal pins of the electronic component.

Here, if an attempt is made to connect the terminal pins P08 and P12 and the terminal pins P14 and P20, the existing wirings 13 and 14 become obstacles, and the design rule check unit 23 generates an alarm signal SA.

In such a case, the operator switches the changeover switch 2 to the temporary wiring side. Then, the temporary wirings L1 and L2 that violate the design rule as indicated by the dotted line in FIG. The temporary wiring does not pass through the design rule check unit 23 and is not interpreted as an error. Therefore, the operator can switch the changeover switch 2 to the actual wiring side again and proceed with the wiring work. In this way, the wiring of all the nets placed on the printed board can be completed once.

The wiring pattern display processing unit 25 can extract data on the graphic data list 32 belonging to, for example, the component surface pattern (level 2) and the hold pattern (level 10) and display the superimposed graphic, so that the actual wiring (for example, red) And a temporary wiring (for example, yellow) can be displayed on the CRT 40 as shown in FIG.

The operator can easily pay attention to the portion of the temporary wiring (yellow), and performs a repair work for removing the wiring failure. A known technique can be used for the operation of correcting the route of the already-wired wiring. For example, when a certain key on the keyboard 1 is pressed, the computer 20 can know that the operation is a correction operation. Then, the end point of the line segment for correcting the cursor as shown in FIG.
When it is arranged at B1 (see FIG. 6), the wiring pattern creation unit 22 can know which net on the graphic data list 32 is issued the correction instruction from the end point coordinates. Then, the two lines (L3, L6) connected to the end point B1 are displayed, for example, in a rubber band, and when the cursor is moved to the point B2 in FIG. 6, the lines L3 and L6 become the lines passing through P07-B2-B3. Become. Next, place the cursor at the point B3 in FIG. 6, press the key for instructing correction on the keyboard 1, and move the cursor to the point B4 in FIG. Will be modified.

Similarly, the lines L4 and L5 (see FIG. 6), which have become obstacles in the wiring connecting the terminal pins P14 and P20, are changed to L4 'and L5' in FIG.
Can be modified as follows.

Thereafter, the changeover switch 2 shown in FIG. 1 is set to the actual wiring side, and all the wiring patterns are actually wired as shown in FIG. To complete the wiring work.

In addition, the configuration and operation for correcting the already-connected wiring are known,
Further, since it is not a main part of the present invention, only a brief description has been given above.

FIG. 1 does not show a plotter or the like for producing a photographic original for manufacturing a printed board based on the printed board data in the graphic data list 32.

<Effects of the Present Invention> As described above, according to the present invention, a wiring pattern that cannot be connected on the design rule due to a path failure is specially displayed as a temporary wiring, and the wiring operation can be advanced. Therefore, a printed circuit board having a uniform wiring density can be designed over the entire area of the printed circuit board. Temporary wiring that violates the design rules is specially displayed on the CRT, and by performing a partial correction that eliminates the path failure in this part, it is possible to realize a well-balanced printed circuit board wiring.

[Brief description of the drawings]

FIG. 1 is a view showing an embodiment of a printed board CAD apparatus according to the present invention, FIG. 2 is a view showing the concept of a net list formed in a storage unit, and FIG. 3 is a view showing an example of a printed board and a wiring pattern. , FIG. 4 is a diagram showing the concept of the graphic data list, FIG. 5 is a diagram for explaining the pattern level, and FIGS.
It is a figure explaining operation of a figure device. DESCRIPTION OF SYMBOLS 1 ... Cursor operation device (tablet), 2 ... Changeover switch, 20 ... Computer, 21 ... Coordinate value reading function part, 22 ... Wiring pattern creation part, 23 ... Design rule check part, 24
... Hold pattern creation unit, 32 ... Figure data list.

Claims (1)

(57) [Claims] 1. A cursor operating device (1) for moving a cursor to an arbitrary position on a CRT, a function (21) for reading a cursor coordinate value, switching means (2) for real wiring and temporary wiring, The means and the output signal of the function (21) are introduced, the start and end point coordinate values of the actual wiring connecting the two points designated by the cursor, a signal indicating the display color of the actual wiring, and indicating the actual wiring. A wiring pattern creation unit (22) for outputting a flag signal, and a design rule that defines a rule for prohibiting printed circuit board wiring; actual wiring already stored in a graphic data list (32) to be described later; A comparison is made between the actual wiring output from the pattern creation unit and a design rule check unit that writes the output data of the wiring pattern creation unit into a graphic data list described later, if the design rule is not violated, The output signal of the function (21) is introduced, the start and end point coordinate values of the temporary wiring connecting the two points designated by the cursor, a signal indicating the display color of the temporary wiring, a flag signal indicating that the wiring is temporary, A pattern data list (32) for storing the output data of the hold pattern generation unit and the output data of the wiring pattern generation unit introduced via the design rule check unit.
And a printed circuit board CAD device equipped with