JPH04323773A - Partial simulator - Google Patents

Abstract

PURPOSE:To simplify the simulation of only a part of a circuit. CONSTITUTION:A partial circuit extracting means 11 shows the circuit diagram stored in a storage means 7 on a user input/output device 2, urges the selection of a partial circuit for the partial simulation, and extracts the circuit information corresponding to the selected partial circuit out of a storage means 3 to store the information in a storage means 4. A boundary attribute input means 12 and an input signal input means 13 input the input/output attributes of the boundary signal names of the partial circuit related to the extracted partial circuit information and the input signals corresponding to the signals names having the input attributes in regard of the input/output attributes through the device 2 to store the signal names and the input signals in a boundary attribute storage means 5 and an input signal storage means 6 respectively. A partial simulation execution means 14 executes the simulation of the partial circuit related to the partial circuit information stored in the means 4 based on the input/output attributes and the input signals stored in both means 5 and 6 respectively. An execution effect output means 15 shows the execution result on the device 2 in the form of a waveform diagram for example.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to circuit design systems such as CAD, and more particularly to a partial simulator for simulating a portion of a certain circuit.

0002

[Background Art] When a conventional simulator is instructed to simulate a circuit such as a logic circuit designed using a circuit diagram creation means, circuit information corresponding to the circuit (such as elements included in the circuit and their connection relationships, etc.) is used. The entire circuit is input from a storage device, etc., and the entire circuit is simulated at once according to input signals for that circuit input separately by the user, and the results are displayed on the screen of the user input/output device. It was meant to be displayed.

0003

[Problem to be solved by the invention] By the way, when performing logic verification using a simulator, there are many cases where it is desired to verify the logic of only a certain part of the circuit in advance, rather than the entire circuit that has been designed. .

[0004] In such cases, conventional simulators cannot simulate only a part of the circuit that has been designed, but instead simulate the entire circuit at once. , it was necessary for the user to separately create a circuit for that part as an independent circuit, and then specify that circuit to run the simulation.

However, with this method, when the number of partial circuits to be simulated increases, management becomes complicated and becomes impractical, and the current situation is that partial simulation is actually given up. . Note that it is possible to simulate the entire circuit and check the logic by focusing on only a certain part from the results, but since the entire circuit is simulated, the simulation time increases, and it is difficult to analyze the execution results. It also takes a lot of time. Such problems become more noticeable as the circuit scale increases.

SUMMARY OF THE INVENTION An object of the present invention is to provide a partial simulator that can easily simulate only a portion of a circuit.

[0007]

[Means for Solving the Problems] In order to achieve the above object, the partial simulator of the present invention includes a partial circuit extracting means for extracting partial circuit information from circuit information according to input from a user input/output device; Boundary attribute input means for inputting an input/output attribute of a signal name of a boundary of a partial circuit related to the extracted partial circuit information from the user input/output device, and a boundary of the partial circuit to which the input attribute is given as the input/output attribute. an input signal input means for inputting an input signal corresponding to a signal name from the user input/output device, and a part for executing a simulation of the partial circuit related to the extracted partial circuit information according to the input input/output attribute and input signal. The apparatus includes a simulation execution means, and an execution result output means for outputting an execution result by the partial simulation execution means to the user input/output device.

Further, in a preferred embodiment of the present invention, the partial circuit extraction means corresponds to a circuit included in a polygonal area designated on the circuit diagram displayed on the screen of the user input/output device. has a configuration for extracting information from the circuit information corresponding to the displayed circuit diagram as partial circuit information, and inputting an input signal by the input signal input means and outputting an execution result by the execution result output means. It has a configuration in the form of a signal waveform diagram.

[0009]

[Operation] In the partial simulator of the present invention, the partial circuit extracting means extracts the circuit information (partial circuit information) concerning the part to be partially simulated from the circuit information concerning the entire circuit according to the input from the user input/output device, The boundary attribute input means inputs the input/output attribute of the signal name of the boundary of the partial circuit related to the extracted partial circuit information from the user input/output device, and the input signal input means receives the input attribute as the input/output attribute. The input signal corresponding to the signal name of the boundary of the subcircuit is input from the user input/output device. Then, the partial simulation execution means executes the simulation of the partial circuit related to the extracted partial circuit information according to the input input/output attributes and input signals, and the execution result output means outputs the execution result by the partial simulation execution means to the user. Output to input/output device.

0010

Embodiments Next, embodiments of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 1, a partial simulator 1 according to an embodiment of the present invention includes a user input/output device 2, a circuit information storage means 3, a partial circuit information storage means 4, a boundary attribute storage means 5, and an input signal storage. Means 6 and circuit diagram storage means 7
It is connected to and internally includes partial circuit extraction means 11, boundary attribute input means 12, input signal input means 13, partial simulation execution means 14, execution result output means 15, and control means 16.

Note that 8 in FIG. 1 is a conventionally known circuit diagram creation means, and by performing interactive processing with this circuit diagram creation means 8 via the user input/output device 2, the user can:
It is possible to generate a circuit diagram of a circuit to be designed and circuit information of the circuit.

The user input/output device 2 is a device equipped with a display device such as a CRT, and input devices such as a keyboard and a mouse, and is used to input various instructions and data to the partial simulator 1 and the circuit diagram creation means 8. User input/output device 2
The output from the partial simulator 1 and the circuit diagram creation means 8 to the user is performed by the user input/output device 2.

The circuit diagram storage means 7 is means for storing the circuit diagram created by the circuit diagram creation means 8, and the circuit information storage means 3 stores circuit information (corresponding to the circuit diagram created by the circuit diagram creation means 8). This is a means for storing information describing elements included in a circuit and their connection relationships.

The partial circuit information storage means 4 is a means for storing information regarding the partial circuits extracted by the partial simulator 1 (partial circuit information).

The boundary attribute storage means 5 is a means for storing the boundary attributes inputted from the user input/output device 2 by the partial simulator 1.

The input signal storage means 6 is means for storing input signals for the partial circuits input from the user input/output device 2 by the partial simulator 1.

The partial circuit extracting means 11 in the partial simulator 1 displays the circuit diagram stored in the circuit diagram storage means 7 on the screen of the user input/output device 2, and performs multiple operations instructed by the user on the screen. Means for extracting circuit information corresponding to the circuit included in the rectangular area as partial circuit information from the circuit information in the circuit information storage means 3 corresponding to the displayed circuit diagram and storing it in the partial circuit information storage means 4. be. In addition,
Instead of actually extracting the circuit information from the circuit information storage means 3, management information indicating which part of the circuit information in the circuit information storage means 3 is set as partial circuit information is stored in the partial circuit information storage means 4. You can also do it.

After extracting the partial circuit, the boundary attribute input means 12 inputs the input/output attribute of the signal name of the boundary of the extracted partial circuit from the user through the user input/output device 2 and stores it in the boundary attribute storage means 5. It is a means of remembering.

After inputting the input/output attribute, the input signal input means 13 transmits the input signal corresponding to the signal name given the input attribute as the input/output attribute from the user input/output device 2 to the user in the form of a waveform diagram, for example. This is a means for inputting the input signal and storing the input signal in the input signal storage means 6.

After inputting the input signal, the partial simulation execution means 14 stores the partial circuit information storage means 4 in accordance with the input/output attributes stored in the boundary attribute storage means 5 and the input signals stored in the input signal storage means 6. It is a means for executing a simulation of a partial circuit related to stored partial circuit information.

The execution result output means 15 is a means for displaying the execution results by the partial simulation execution means 14 on the screen of the user input/output device 2 in the form of a waveform diagram.

The control means 16 is a means for controlling each part of the partial simulator 1 and the user input/output device 2.

FIG. 2 is a flowchart showing the steps of a user when logically verifying a certain part of a certain circuit using the partial simulator 1 shown in FIG. 1. The operation of the partial simulator 1 will be explained.

The user specifies a circuit including the partial circuit to be simulated and instructs the partial simulation to be performed from the user input/output device 2 (S1 in FIG. 2).

When this instruction is input, the control means 16 of the partial simulator 1 activates the partial circuit extraction means 11 for the designated circuit.

The partial circuit extraction means 11 reads the circuit diagram of the specified circuit from the circuit diagram storage means 7, displays it on the screen of the user input/output device 2 through the control means 16,
Prompt the user to specify the partial circuit. Note that if the user wants to perform a partial simulation on a certain part of the circuit diagram created on the screen of the user input/output device 2 using the circuit diagram creation means 8, since the circuit diagram is already displayed, The above operations are omitted.

FIG. 3 shows an example of a circuit diagram displayed on the screen of the user input/output device 2, in which the entire circuit diagram of a designated circuit is displayed using symbols corresponding to each element. Note that NET1 to NET9 in the figure are signal names.

Next, the user specifies the target portion by pointing to each vertex of the polygon surrounding the portion to be logically verified using a pointing device such as a mouse provided in the user input/output device 2 (step S2 in FIG. 2). ).

Assuming that points P1 to P8 in FIG. 3 are sequentially designated by this operation, the partial circuit extracting means 11 extracts points P1 to P8 in FIG. Recognize the circuit shown as a partial circuit,
Circuit information corresponding to this is extracted from the circuit information storage means 3 that stores circuit information corresponding to the displayed circuit diagram and stored in the partial circuit information storage means 4. Further, only a partial circuit is displayed on the screen of the user input/output device 2 as shown in FIG. 4 instead of the display shown in FIG. Then, the boundary attribute input means 12 is activated.

Next, the user indicates the boundary of the partial circuit as shown in FIG. 4 using a pointing device such as a mouse, and NET1 is I (input), NET2 is I (input)
,..., NET9 assigns input/output attributes such as O (output) (S3 in FIG. 2).

The boundary attribute input means 12 inputs the input/output attributes assigned to each of these signal names through the control means 16, and stores them in the boundary attribute storage means 5. Then, the input signal input means 13 is activated.

When the input signal input means 13 is activated, it inputs what kind of input signal for the signal names NET1, NET2, etc. whose input/output attribute input by the boundary attribute input means 12 is the input attribute (I). The user is asked via the control means 16 if the user is interested in the information, and is prompted to input the information. The user inputs input signals accordingly (S4 in FIG. 2).

At this time, for example, the input signal input means 13 inputs the input signal in the following manner. That is, a time chart diagram in which signal names are arranged vertically and the time axis is horizontally displayed (for example, a diagram such as the one shown in FIG. 5 described later) is displayed on the screen of the user input/output device 2, and the user can read the time chart As input waveforms are input on the time axis of the signal name whose input/output attribute is input (I) on the diagram, information on the input signal indicated by the input waveform is acquired and stored in the input signal storage means 6. It is something.

Now, when inputting the input signals is completed, the user instructs execution of a partial simulation from the user input/output device 2 (S5 in FIG. 2). As a result, the control means 1
6 activates the partial simulation execution means 14.

When the partial simulation execution means 14 is activated, the partial simulation execution means 14 executes the partial simulation according to the input/output attribute of the boundary of the partial circuit stored in the boundary attribute storage means 5 and the input signal for the partial circuit stored in the input signal storage means 6. A simulation of the partial circuit represented by the partial circuit information stored in the circuit information storage means 4 is executed, and the execution result is notified to the execution result output means 15.

The execution result output means 15 displays the execution results of the partial simulation execution means 14 on the screen of the user input/output device 2 through the control means 16.

FIG. 5 shows an example of a partial simulation execution result displayed on the screen of the user input/output device 2. In the figure, NET1 to NET9 are signal names of boundaries of partial circuits, which match the signal names in FIGS. 3 and 4. Further, (I) and (O) next to it are input/output attributes of the signal name, which are the same as the input/output attributes input by the user in step S3. The waveforms drawn parallel to the time axis scale next to each signal name are the input waveform of the input signal input by the user and the output waveform of the partial circuit obtained as a result of the partial simulation.

The user analyzes the partial simulation execution results as shown in FIG. 5 (S6 in FIG. 2) and performs logic verification of the partial circuit. Then, it is determined whether it is necessary to continue the partial simulation for a different input signal (S7 in FIG. 2), and if necessary, the process returns to step S4 and the above-described operations are repeated. Furthermore, when finishing the partial simulation for the relevant partial circuit, it is determined whether or not to perform partial simulation for other partial circuits (S8 in FIG. 2), and when performing partial simulation for other partial circuits, return to step S1. and repeat the above operation. Furthermore, if no other partial simulation is to be performed, the operation is ended.

[0040]

[Effects of the Invention] As explained above, by using the partial simulator of the present invention, it is possible to perform a simulation limited to a certain part of a designed circuit, which is a simple method of specifying the part of the entire circuit that is to be partially simulated. It is effective and can be easily implemented. This enables flexible logic verification and greatly improves the efficiency of circuit design.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a flowchart showing a user's procedure when performing a partial simulation.

FIG. 3 is a diagram showing an example of displaying a circuit diagram and selecting a partial circuit.

FIG. 4 is a diagram showing extracted partial circuits.

FIG. 5 is a diagram showing an example of partial simulation execution results.

[Explanation of symbols]

1... Partial simulator 11...Partial circuit extraction means 12... Boundary attribute input means 13...Input signal input means 14...Partial simulation execution means 15...Execution result output means 16...Control means 2...User input/output device 3...Circuit information storage means 4...Partial circuit information storage means 5... Boundary attribute storage means 6...Input signal storage means 7...Circuit diagram storage means 8...Circuit diagram creation means

Claims (3)

[Claims] 1. Partial circuit extraction means for extracting partial circuit information from circuit information according to input from a user input/output device, and input/output attributes of signal names of boundaries of partial circuits related to the extracted partial circuit information. Boundary attribute input means for inputting from the user input/output device; and input signal input means for inputting from the user input/output device an input signal for a signal name of a boundary of a partial circuit to which an input attribute is given as the input/output attribute. a partial simulation execution means for executing a simulation of the partial circuit related to the extracted partial circuit information according to the input input/output attributes and input signals; A partial simulator comprising: an execution result output means for outputting an output to a partial simulator. 2. The partial circuit extracting means extracts information corresponding to a circuit included in a polygonal area designated on the circuit diagram displayed on the screen of the user input/output device as partial circuit information. 2. The partial simulator according to claim 1, wherein the partial simulator has a configuration for extracting circuit information from circuit information corresponding to a generated circuit diagram. 3. The partial simulator according to claim 2, wherein input of the input signal by the input signal input means and output of the execution result by the execution result output means are performed in the form of a signal waveform diagram.