JPS63231677A - Method for restoring logic circuit diaphragm - Google Patents

Abstract

PURPOSE:To eliminate the unnecessary folding of wiring and to restore a logic circuit diagram that a designer easily understands by recognizing a shift in terminal position between two logic gates to be connected and adjusting the arrangement positions of those logic gates. CONSTITUTION:When the output terminal of one of two logic gates 2-4 and 1 is connected to one specific input terminal of the other logic gate, the deviation yb-ya in height between both terminals is detected and both terminals are arranged and adjusted on the same straight line and connected. Namely, the two logic circuits 2-4 and 1 to be connected to each other are arranged in two adjacent grids and their positions are so adjusted that the output terminal of one logic circuit and one specific input terminal of the other logic circuit are on the same straight line. Consequently, a connecting line from the output terminal of one logic circuit to the specific input terminal of the other logic circuit has no folded part and the logic gates are arranged freely irrelevantly to the wiring of a grid image; and the drawing is simplified and the logic circuit diagram which is easy for the designer to understand and see can be restored.

Description

[Detailed Description of the Invention] [Summary] In a method for restoring a logic circuit diagram from logic circuit connection information, a shift in the terminal positions of two connected logic gates is recognized and the arrangement positions of those logic gates are adjusted. This eliminates unnecessary bends in the wiring, making it possible to restore a logic circuit diagram that is easy for designers to understand.

[Industrial application field]

The present invention relates to a method for restoring a logic circuit diagram, and particularly to a method for restoring a logic circuit diagram from mask pattern data (artwork data) using a computer.

In the layout design of large-scale integrated circuits (LSI), errors may occur in the design results because highly complete layout designs and partial corrections to the results of automatic layout are performed manually. Therefore, in order to detect errors in the artwork data resulting from layout design, it is necessary to restore the logic circuit diagram from the connection information of the artwork data.

[Conventional technology]

The method for restoring a logic circuit diagram in 2-1 involves registering the symbols of each logic gate in advance as an image in a library, and placing the symbols of each logic gate obtained based on the artwork data on the drawing to create a logic circuit diagram. was being restored.

Examples of the registered logic gate symbols include the inverter 1 shown in FIG. A logic gate consisting of a NOR circuit 4, and further N
AND circuit (2-person power)

(3-man power, 4-man power, etc.).

In this way, the logic circuit diagram restored from the artwork data is indispensable for visual inspection of circuit diagrams and feedback of matching results to circuit diagrams during automatic matching.

[Problem that the invention seeks to solve]

In conventional logic circuit diagram restoration methods, it is not possible to place logic gates at arbitrary positions on the drawing, but they must be placed in one of the preset matrix-like placement areas (this is called a "grid"). Ta. This is done to facilitate the determination of the arrangement of logic gates after recognizing the connections of the logic circuits, and to make the circuit diagram easier to understand by arranging the logic gates in a regular manner.

However, on the other hand, wires that could be drawn straight by humans could sometimes become bent because computers require logic gates to be placed on a grid.

For example, if connection information is given to connect the output terminal of the logic gate shown in FIG. 3(B) to the input terminal of the logic gate (inverter) shown in FIG. 3(A), according to the conventional method, As shown in Figure 4, place the origin position (×
(indicated by marks) are positioned on the same horizontal plane 115. Therefore, the height ya between the output terminal of the logic gate shown in FIG. 3(A) and the origin is different from the height yb between the output terminal of the logic gate and the origin shown in FIG. 3(B). In the case of the connection, as shown by 6 in Figure 4, (yb -ya
), which resulted in a bent part with a height of 100.0 cm, making the restored logic circuit diagram difficult to understand.

The present invention was created in view of the above points, and an object of the present invention is to provide a method for restoring a logic circuit diagram that can eliminate unnecessary bends in wiring.

[Means for solving problems]

In the logic circuit diagram restoration method of the present invention, when connecting an output terminal of one of two logic gates to a predetermined input terminal of the other logic gate, the difference in height between both terminals is is detected, and both terminals are arranged and connected on the same straight line.

[Effect]

Two logic circuits that are connected to each other are arranged in two adjacent grids, and the output terminal of one logic circuit and one predetermined input terminal of the other logic circuit are located on the same straight line. The position adjustment is performed as follows.

Therefore, it is possible to prevent a bend from occurring in the connection between the output terminal of one logic circuit and a predetermined input terminal of the other logic circuit.

〔Example〕

FIG. 1 shows a flow chart for explaining the operation of an embodiment of the present invention. First, based on the logic circuit connection information of the artwork data, it is recognized which logic gates are to be connected (step S1), and then the logic gates are arranged in the grid (step Sz).

In the conventional method, the wiring was processed immediately after this, resulting in a bent part in the wiring as shown by 6 in FIG. Recognizing the misalignment of logic gate terminals (
Step S3). That is, in the present invention, the distance from the origin in the y direction (the direction perpendicular to the direction of the input/output signal line, also referred to as the height direction) is stored in advance as data for all terminals of each logic gate that forms the library. given, and when connecting the output terminal of the first logic gate to the input terminal of the second logic gate (if there are multiple input terminals, the predetermined one input terminal to be connected among them), the above Recognize the height difference between the output terminal and the input terminal.

Next, either one of the first and second logic gates is moved in the height direction by the amount of the deviation in the height direction to make the deviation zero, and the output terminal and the predetermined input terminal are connected to each other. After adjusting so that they are located on the same straight line, wiring is performed (step St).

Next, the processes of steps S3 and S4 described above are performed for all two connected adjacent logic gates, and the completed invasion process is completed (step Ss).

Therefore, according to this embodiment, if connection information is obtained that connects the output terminal of the logic gate shown in FIG. 3(B) to the input terminal of the logic gate shown in FIG. 3(A), the step The terminal deviation recognized in S3 is (Vb - Va
), and when considering the logic gate shown in FIG. 3(B) as a reference, the inverter 1 is located below by the above-mentioned shift as shown in FIG.

Therefore, by the process of step S4 in FIG. 1, (yb - ya) is added to the y coordinate of the library arrangement of the inverter 1 shown in FIG. Move and connect the wires. As a result, according to this embodiment, as shown in FIG.
It is possible to restore a logic circuit diagram without bent wiring.

In the case of the above logic circuit diagram, the same effect can be obtained even if inverter 1 is considered as a reference, and in this case, the y coordinate of the output terminal of the logic gate shown in FIG. 3 (8) is (Va-yb').
Wiring is performed by trimming by the amount shown in Fig. 3 (B).
) is wired so that it is shifted downward by (yb - ya) in the y direction with respect to the inverter 1. ).

〔Effect of the invention〕

As described above, according to the present invention, bends in the wiring are eliminated by performing placement that recognizes the positional relationship of the terminals, so logic gates can be placed freely without being tied to grid image wiring. , the drawings are simplified and the logic circuit diagram can be restored in a way that is easy for the designer to understand and see.

[Brief explanation of drawings]

FIG. 1 is a 70-wire diagram for explaining the operation of an embodiment of the present invention, FIG. 2 is a logic circuit diagram of an example restored by the present invention, and FIG. 3 is a diagram showing each logic gate registered as a library. , FIG. 4 is an example of a logic circuit diagram restored by the conventional method. In the figure, 1 is an inverter, 2.3 is an AND circuit, 4 is a NOR circuit, and SI to S5 are steps. iI4 figure

Claims (1)

[Claims] A method for restoring a logic circuit diagram using a computer based on connection information of logic circuits, comprising: one of two logic gates arranged and connected to two adjacent grids according to the connection information; When connecting an output terminal of a logic gate to a predetermined one input terminal of the other logic gate, detect a height difference between the output terminal and the predetermined one input terminal when arranged on the grid. . A method for restoring a logic circuit diagram, comprising adjusting and connecting the output terminal and the predetermined one input terminal on the same straight line so as to make the detected deviation zero.