JP2783709B2 - Logic circuit design equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interactive logic circuit designing apparatus for designing a logic circuit on a screen.

[0002]

2. Description of the Related Art In a conventional interactive logic circuit design apparatus for designing a logic circuit, as shown in FIG. 12, a designer arranges a symbol figure 50 representing a logic element on a drawing and arranges the arranged symbol figure. The logic circuit diagram is created by connecting the 50 with each other by a line segment graphic 51. Further, in a logic circuit design apparatus using this kind of graphic information, logic connection information is extracted from a created logic circuit diagram, and the extracted logic connection information is used for manufacturing an electronic circuit or the like. In the above-described logic circuit diagram, there may be a logic element having an input terminal which is logically fixed by being connected to a power supply or a ground, a logic element having a terminal which is not connected to anywhere, or the like. Such a logic element can be converted into a simpler circuit without changing the function of the logic circuit by replacing the logically meaningless terminal with a logic element having a simpler function.

For example, 3 having an input terminal connected to a power supply
In the case of the symbol figure of the input AND element (the symbol figure 22a requiring replacement), since the terminal 24C is connected to the power supply and fixed at the logic "1", two symbol figures 22a requiring replacement are input. The circuit can be changed to a simpler logic circuit having the same function by replacing with a logical product element. This change is replaced with 2 input symbol graphic AND gate, such as a symbol graphic 22a in FIG. 13 the symbols figure 22a which requires replacement of Figure 2, the symbol graphic 2
The power supply symbol figure (power supply 25 in FIG. 2) connected to 2a and the line figure connecting the power supply symbol figure and the 2-input AND element symbol figure are deleted, and the 3- input logic replaced. In order to perform the same operation as the AND element, the symbol figure of the replaced two-input AND element and the symbol figure of the other two-input AND element and the other logical element are reconnected by using a line segment figure. Was.

[0004]

In the conventional logic circuit designing apparatus, since a specific position on a symbol figure represents a connection terminal of a logic element, the symbol figure of the logic element is simply replaced with another symbol figure without any restrictions. With only replacement, it is not possible to guarantee a graphic overlap between the position on the symbol representing the terminal and the line segment for connection.
It is necessary to add and delete line segment figures. In addition, the operation of adding a connection line segment figure depends on how to write each logical form and is complicated, so that there is a problem that it is difficult to automatically perform arrangement processing. Furthermore, if only the logical connection information extracted from the logic circuit diagram is changed without changing the logic circuit diagram, there is a problem that the correspondence between the logic circuit diagram and the logical connection relationship is lost.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and can automatically replace a logic element on a logic circuit diagram to change to a simpler logic circuit diagram. It is an object to obtain an efficient logic circuit design device.

[0006]

Means for Solving the Problems] logic circuit designing apparatus according to a first aspect of the invention, as shown in FIG. 1, Shin logic element
The has air terminal other than Bol figure, the biasing pressure figures such as a power supply 1
Is replaced with a second symbol graphic not having the additional graphic, the same symbol position as the input / output terminal position from the origin on the screen of the first symbol graphic before the replacement. A symbol graphic generating means for generating a second symbol graphic; and replacing the second symbol graphic with an input / output terminal position from an origin on a screen on which the first symbol graphic was placed before replacement. Replacement editing means 3 for replacing the symbol graphic and deleting the unnecessary graphic which has become unnecessary. As shown in FIG. 6, the logic circuit designing apparatus according to the second aspect of the present invention further includes a second symbol graphic generated by the symbol graphic generating means, in addition to the configuration of the logic designing circuit of the first invention. Is stored.

[0007]

[Action] logic circuit design device in the invention of claim 1,
Check terminal other than the symbol graphic logic elements, the first symbol graphic having an urging pressure figures such as a power supply, when replacing the second symbol shapes without the addition figures, before replacement symbol figure generating means A second symbol graphic having the same input / output terminal position as the input / output terminal position from the origin on the screen of the first symbol graphic is generated, and the second symbol graphic is replaced by the replacement editing means.
Is replaced with the input / output terminal position from the origin on the screen where the first symbol graphic was placed before the replacement, and the additional graphic which became unnecessary by replacing the symbol graphic was deleted and edited. I do. Logic circuit design device in the invention of claim 2 stores the second symbol figure generated by said symbol figure generating means in the symbol graphic storage means,
When replacing with the first symbol figure, the symbol figure stored in the symbol figure storage means is used.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a functional block diagram of a logic circuit design apparatus showing an embodiment of the first invention, and FIGS. 2 to 5 are diagrams showing a replacement process. In FIG. 1, 1 is a screen, 2 is a symbol figure generating means, and 3 is a replacement editing means. 2 of FIG.
Reference numeral 2a denotes a symbol figure of an AND element requiring replacement as the first symbol figure, and reference numeral 22b in FIG. 4 denotes a generated symbol figure as a second symbol figure to be replaced with the first symbol figure.

[0009] Symbol figure generating means 2, the symbol pattern of three-input logical product element before substitution in screen 1 (FIG. 2), air terminals, with pressure figures such as a power supply, i.e., the symbol graphic 22a that requires replacement A second symbol graphic having no terminal connected to the additional graphic such as the line segment graphic 23 connected to the terminal 24C and the power supply 25 is created. In the case of creation, the data of the symbol graphic 22a requiring the replacement between the symbol graphics 21 not requiring the replacement in FIG. 2 is extracted, and the generated symbol graphic 22b to be replaced is generated. The terminal positions of the generated symbol graphic 22b in FIG. 4 are the same as the coordinates of the input terminals 24A and 24B and the output terminal 24Y of the symbol graphic 22a requiring replacement from the origin.

[0010] The replacement editing means 3 is a symbol figure generating means 2
2 are replaced with the terminals 24A, 24B, 24 of the symbol graphic 22a requiring replacement in FIG.
Replace with the same position as the coordinate from the origin of Y, and delete the additional graphic such as the line graphic 23 and the power supply 25 connected to the terminal C of the symbol graphic 22a. Next, the operation of the logic circuit designing apparatus according to the first invention will be described.
The symbol graphic 22a requiring replacement in FIG.
4C is connected to a power supply 25 by a line segment graphic 23,
The logic is fixed to the signal "1". First, the control unit (not shown) transmits the symbol graphic 22a (3
Input AND gate), based on substitution rules 3 input logic elements that had been separately prepared with information terminal 24C is connected to the power supply 25, the symbols of the two-input AND gate, except for the biasing pressure figures Decide to replace. At this time, the correspondence between the terminal of the two-input AND element and the terminal of the three-input AND element is also determined.

Next, in response to an instruction from a control unit (not shown),
The symbol graphic generating means 2 generates a (generated) symbol graphic 22b of a two-input AND element as shown in FIG. When the symbol graphic is generated, the positions of the terminals 24A, 24B, and 24Y of the generated symbol graphic 22b from the origin of the symbol graphic are the origins of the terminals 24A, 24B, and 24Y of the symbol graphic 22a requiring replacement in FIG. So that it is the same as the position from. Next, as shown in FIG. 3, the replacement editing means 3 is connected to the symbol graphic 22a requiring replacement and the terminal 24C of the symbol graphic 22a .
Power supply 25 is-added figure, remove the line segment figure 23. Then, the symbol graphic generated by the symbol graphic generating means 2 is replaced with the symbol graphic 22a 24A,
4B and 24Y are arranged at the same coordinates. As a result, the symbol figure is replaced as shown in FIG. As described above, the terminal A of the symbol graphic 22a requiring the replacement,
This means that the three-input AND element is replaced with the two-input AND element without changing the additional graphic and the line graphic connected to B and C. The deletion of the line figure may be performed before or after the replacement of the symbol figure.

FIG. 6 is a functional block diagram of the logic circuit designing apparatus according to the second invention, and FIG. 7 is a specific example of the symbol graphic stored in the symbol graphic storage means of FIG. In FIG. 6, reference numeral 4 denotes a symbol graphic storage means. The symbol graphic storage means 4 is further provided in the logic circuit design apparatus of the first invention. 7 (a) to 7 (e) created by the symbol figure generating means 2 in advance.
Is stored. Of course, FIG.
The positions of the coordinates of the terminals A, B, C, and Y in (a) to (e) correspond to the terminals 24 of the symbol graphic 22a requiring replacement in FIG.
This is the same as the position of the coordinates of A, 24B and 24Y.

In the above-described embodiment, the case where a logic element having a logic-fixed input terminal is replaced with another logic element has been shown as an example. The terminal 30 of the logic element not connected to
And the logical functions of the terminal and the element are the same as shown in FIGS.
Can be applied to the symbol graphic 41 of FIG. 10, that is, the symbol graphic of another element having different electrical characteristics. Further, the present invention can also be applied to a case where all the terminals of a logic element are not connected to any part and an element unnecessary for a logic circuit is deleted.

[0014]

As described above, according to the first aspect of the present invention, in addition to the symbol figure of the logic element, a vacant terminal, a power supply, etc.
Output of the first symbol graphic having an urging pressure figures, when replacing the second symbol shapes without the additional figures, from the origin of the screen on which a first symbol graphic was located before substitution Since the second symbol graphic having the same input / output terminal position as the terminal position is generated in advance, and replaced with the input / output terminal position from the origin on the screen where the first symbol graphic was placed before replacement, Since the position of the symbol figure to be replaced on the screen does not change, it is only necessary to replace the symbol figure and delete the unnecessary figure, so that the replacement can be performed quickly and the efficiency of the logic design can be increased. Further, according to claim 2
According to that invention, since a configuration for previously storing a second symbol shapes, than the invention according to claim 1, there is an effect that can shorten the time required for further substitution.

[Brief description of the drawings]

FIG. 1 is a functional block diagram of a logic circuit design apparatus showing one embodiment of the first invention.

FIG. 2 is a diagram showing a replacement process by the apparatus of FIG. 1;

FIG. 3 is a diagram showing a replacement process similarly to FIG. 2;

FIG. 4 is a diagram showing a replacement process similarly to FIG.

FIG. 5 is a diagram showing a replacement process similarly to FIG. 2;

FIG. 6 is a functional block diagram of a logic circuit design apparatus showing one embodiment of the second invention.

FIG. 7 is a view showing a symbol figure stored in a symbol figure storage means of FIG. 6;

FIG. 8 is a diagram showing an application example of the replacement by the devices of the first and second inventions.

FIG. 9 is a diagram showing an application example similarly to FIG.

FIG. 10 is a diagram showing an application example similarly to FIG.

FIG. 11 is a diagram showing an application example similarly to FIG.

FIG. 12 is a diagram showing a graphic displayed on a screen showing an example of a conventional technique.

FIG. 13 is a diagram showing a figure displayed on the screen as in FIG. 12;

[Description of Signs] 1 screen 2 symbol figure generating means 3 replacement editing means 4 symbol figure storing means 22a symbol figure requiring replacement 22b generated symbol figure

Claims (2)

(57) [Claims] A logic circuit for interactively designing a logic circuit by arranging symbol graphics of a plurality of logic elements on a screen and interconnecting these symbol graphics with one or more line graphics. In the design equipment, the logic element
The has air terminal other than Bol figure, the biasing pressure figures such as a power supply 1
Is replaced with a second symbol graphic not having the additional graphic, the same symbol position as the input / output terminal position from the origin on the screen of the first symbol graphic before the replacement. A symbol graphic generating means for generating a second symbol graphic, and replacing the second symbol graphic with an input / output terminal position from an origin on a screen on which the first symbol graphic was placed before replacement. A logic circuit design apparatus, comprising: a replacement editing unit that replaces a symbol figure and deletes the unnecessary figure that has become unnecessary. 2. A method according to claim 1, further comprising the step of storing a symbol graphic storing means for storing the second symbol graphic generated by the symbol graphic generating means, wherein the second symbol graphic is replaced with the first symbol graphic on a screen. 2. The logic circuit designing apparatus according to claim 1, wherein the replacement is performed by the replacement editing means using the second symbol graphic stored in the symbol graphic storage means.