JPS6378271A - Cad unit having simulation function - Google Patents

Abstract

PURPOSE:To analyze the result of simulation easily without involving troublesome confirming work by displaying the result of simulation and the result basing on comparison with an expected value is specified different color. CONSTITUTION:Simulation for test data TDn corresponding to an optional pin Pn is executed by a simulation executing means 3. At this time, the result of simulation SIM is displayed on the picture of a display unit in specified color through a display controlling means 5. The preset expected value is compared with the result SIM by a comparator 4, and when they are discordant, the result of discordance is displayed in color different from the specified color. Accordingly, an operator can confirm the result of comparison between the preset expected value and the result SIM every time simulation is executed on the picture of the means 2.

Description

[Detailed Description of the Invention] [Summary] A CAD device with a simulation function that generates test data (TDn) corresponding to any specified pin (Pn).
), the simulation result (SIM) is displayed in a predetermined color on the display means (2), and if the simulation result (SIM) does not match the preset expected value, the discrepancy result is displayed. By displaying the color in a color different from the predetermined color, analysis of the simulation results is facilitated.

[Industrial application field]

The present invention relates to a CAD (computer-aided design) device with a simulation function, and more specifically, the present invention relates to a CAD (computer-aided design) device with a simulation function, and more specifically, when designing a logic IC (integrated circuit) such as a gate array or standard cell, or a logic LSI (large-scale integrated circuit).
Alternatively, the present invention relates to a CAD device having a function of performing simulation on test pattern data corresponding to any designated pin among external terminal pins of a logic LSI.

[Prior art and problems to be solved by the invention]

2. Description of the Related Art Techniques for designing logic ICs or logic LSIs using CAD devices, or more broadly CAD systems, have been known for a long time. In this case, -m is interactive (i
A CAD system based on the interactive method is used. This method uses a human (operator) and a computer (
Design is proceeded through dialogue between computers (computers).For example, the editing of test data for logic simulation is explained as follows. First, when the operator defines the test data name from the keyboard,
The computer requests the pin name of the IC or LSI on the display screen. In contrast, the operator inputs data indicating any pin, that is, VCC (power supply>, D<
data), B (bus), etc. pin names and attributes of the pins,
, the computer requests test pattern data corresponding to the pin on the display screen. On the other hand, when the operator inputs test pattern data through key operations, the computer edits the test pattern data through internal processing. In this way, by using the interactive method, the efficiency of editing test data is improved.

When this test data editing stage is completed, test data simulation is performed, but according to conventional CAD systems, simulation is first performed on the test data of each pin, and the results are temporarily stored in a register etc. inside the computer. The simulation results are then output to the outside on a display screen or in the form of a hard copy by the operator performing key operations as necessary. Therefore, when analyzing simulation results, pins with attributes for signal output,
For example, it is necessary to compare simulation results and expected values while referring to a trace list in which expected values corresponding to D (data), B (bus) in signal output mode, etc. are written in advance.

In this case, it is necessary to check the data value of each pin at each point in time based on the message, which takes time and effort, making the work extremely troublesome, and making it difficult to simulate/analyze the results. There was a problem.

The present invention was created in view of the problems in the prior art described above, and an object of the present invention is to provide a CAD device with a simulation function that facilitates analysis of simulation results.

[Means for solving problems]

Figure 1 shows a CAD with simulation function according to the present invention.
A principle block diagram of the device is shown.

In FIG. 1, 1 is a data input means for specifying an external terminal pin Pi of the integrated circuit and inputting corresponding test data TDi into the pin, and 2 is a display having a color display function. It is a means.

Reference numeral 3 denotes simulation execution means, which has a function of executing a simulation on test data TDn when the corresponding test data TDn is input to any pin Pn specified by the data input means 1. Reference numeral 4 denotes a comparison means, which is used to compare a preset expected value corresponding to the above-mentioned pin Pn and the simulation result SIM executed by the simulation execution means 3.

Reference numeral 5 indicates a display control means for controlling the display means 2, which displays the simulation result SIM on the screen in a predetermined color at the time the simulation is executed, and also displays the simulation result SIM if it does not match the above-mentioned expected value. It has a function of displaying the mismatch result in a color different from the predetermined color when the mismatch occurs.

[For production]

In the CA and D devices with simulation functions according to the present invention, test data TDn corresponding to any pin Pn
When a simulation is executed by the simulation execution means 3, the SIM result of this simulation is displayed in a predetermined color on the screen of the display means 2 via the display control means 5. In addition, the expected value set in advance and the simulation result SIM
If the two do not match based on the comparison (comparison means 4), the result of the mismatch is displayed in a color different from the above-mentioned predetermined color.

Therefore, the operator can display the simulation result S on the screen of the display means 2 every time a simulation is executed.
You can check the comparison results between the IM and the preset expected value and the simulation result SIM, and both are displayed on the screen in different colors.
Increased recognition of displayed data. In this manner, the apparatus of the present invention facilitates analysis of simulation results without any troublesome work.

〔Example〕

FIG. 2 shows a schematic system configuration of a CAD device with a simulation function as an embodiment of the present invention.

In the figure, 20 is a system bus consisting of a data bus, a control bus, etc., and the keyboard 2 is connected via this bus 20.
1, a display 22, a memory 23, an MPU (microprocessor unit) 24, and a mouse 25 are connected to each other.

In addition to normal keys such as a numeric keypad and alphabet keys, the keyboard 21 can also be used to change and delete data displayed on the screen of the display 22.
, insert, move, etc. are provided. This keyboard 21 is for inputting data indicating an external terminal pin of an IC or LSI and test data data corresponding to this pin, and corresponds to the data input means 1 shown in FIG. do.

The data that indicates the pin is the bin name, for example, cc (power supply), GK (clock), A (address), D (data).
, B (bus), etc., and its attribute, that is, the designation of 1 (for signal input) or O (for signal output). only is entered. On the other hand, regarding the test pattern data, the timing is set on the screen of the display 22 using the direction keys, and the test pattern data is input using the numeric keypad and alphabet keys.

The display 22 has a color display function, and displays each data input from the keyboard 21 or the MPU 24.
Various data processed by is displayed on the screen in a predetermined color. This display 22 corresponds to the display means 2 shown in FIG. The memory 23 stores various data input from the keyboard 21 in addition to programs representing processing performed by the MPU 24, and also stores data input from the keyboard 21, and also stores data corresponding to pins having attributes for signal output, such as B, etc. Expected values are set and stored in advance.

The basic function of the MPU 24 is to execute predetermined processing based on a program stored in the memory 23. As one function of the MPU 24 in this embodiment, when corresponding test data is input to an arbitrary pin specified by the keyboard 21, the MPU 24 executes a simulation on the test data.

Among other functions, the MPU 24 compares the results of the executed simulations with preset expected values corresponding to any of the pins mentioned above. Furthermore, as another function, MPU
24 displays the simulation result in a predetermined color (green in this embodiment) on the screen of the display device 22 when the above-mentioned simulation is executed, and if the simulation result does not match the above-mentioned expected value. has a function of displaying the mismatch result in a color different from the above-mentioned predetermined color (pink in this embodiment).

This MPIJ 24 corresponds to the simulation execution means 3, comparison means 4, and display control means 5 shown in FIG.

The mouse 25 is used to specify the position on the screen of the display 22 based on manual operation.

FIG. 3 shows a flowchart for explaining the simulation performed by the CAD apparatus shown in FIG.

First, in step 301, the number of pins N of the IC or LSI is
and the initial setting of the variable n are performed. Step 302
Then, a bin (Pn) name such as B is specified. In step 303, the final time T is set and the variable i is initialized. The final time point T refers to the time point corresponding to the final pattern when it is assumed that the test pattern data of the pin to be simulated consists of a plurality of patterns in time series. In the next step 304, the expected value corresponding to the pin is set, and in the next step 30
5, the test data at time 11, ie pin P in this case, at time 1.5. A test pattern corresponding to is input. Steps 301 to 305 are the keyboard 2
It is executed by manual key operation from 1 onwards. Furthermore, time point 1
The variable i assigned to 1 follows the chronological order, but the pin name P
The variable n assigned to n does not follow the order in which the bins are arranged, but follows the order in which the bins are specified by the operator.

In step 306, a simulation at time point 11 is executed, and in the next step 307, the result of the simulation is displayed in green on the screen of the display 22.

In addition, when displaying the simulation results, the pin name is also displayed, and this pin name is displayed in blue in order to improve the recognition level of the displayed data.
At step 8, it is determined whether the simulation result matches the above-mentioned expected value (YES) or not (NO). This determination is made by the MPIJ 24 reading out the expected value corresponding to the bin P from the memory 23, and using the read expected value and the display 22.
This is done by comparing the simulation results displayed on the screen, but if the judgment is Y.
If the determination is ES, the process jumps to step 310, and if the determination is No, the process advances to step 309. In step 309, information indicating that the expected value and the simulation result do not match as a strobe error is displayed in pink on the screen of the display 22. In the actual display format, this information is displayed as a "pink frame" surrounding the expected value displayed on the screen. Steps 306-30
9 is executed by the MPU 24.

In step 310, the time ti reaches the final time T (Y
ES) or not (NO) is determined. If the determination is YES, the process jumps to step 312, and if the determination is NO, the process advances to step 311. In step 311, the value of variable i is incremented (1=2 in this case), and the process returns to step 305. On the other hand, in step 312, it is determined whether the value of the variable n is equal to the value of the number of pins N (YES) or not (No). If the determination is YES, the flow ends; if the determination is NO, The process proceeds to step 313. In step 313, the value of n is incremented (n=2 in this case), and the process returns to step 302.

As mentioned above, each time a simulation is executed, the simulation results are displayed in color (
Since the strobe error based on the comparison between the expected value and the simulation result is displayed in a different color (pink) on the screen of the display 22, it is possible to improve the recognition of the displayed data. , simulation results can be easily analyzed.

FIG. 4 shows an example of the display of simulation results on the display 22 of the apparatus shown in FIG. In Figure 4, DS
P indicates the screen of the display 22, characters in area B (displayed in blue) represent pin names, and numbers at the left end of area W (displayed in white) represent respective points in time on the test pattern data. The simulation results are displayed on the screen at each change point of the signal value, and the display is “O”, “1”, and “X”.
It is represented by characters such as. Here, "0" is LOW
The state, "1" represents the old GH state, and "X" represents the undefined state. Signal values are displayed in green (area G), and changed values are displayed in yellow (area Y). Furthermore, a strobe error is displayed as a pink frame (vJ area P). Note that the characters within the pink frame are the expected values, and the simulation results are indicated by the characters at the previous time.

〔Effect of the invention〕

As explained above, according to the present invention, the simulation results are displayed on the screen in a predetermined color at the same time as the simulation is executed, and the results based on the comparison between the simulation results and the expected values are displayed on the screen in another predetermined color. Since it is displayed, simulation results can be easily analyzed without any troublesome confirmation work.

[Brief explanation of the drawing]

Fig. 1 is a principle block diagram of a CAD device with a simulation function according to the present invention, Fig. 2 is a system configuration diagram showing an embodiment of the present invention, and Fig. 3 is a diagram for explaining the simulation by the CAD device of Fig. 2. FIG. 4 is a flowchart showing an example of the display of simulation results on the display 22 of the device shown in FIG. (Explanation of symbols) 1...Data input means, 2...Display means, 3.
...Simulation execution means, 4...Comparison means, 5
...Display control means, Pi, Pn...pin,
TDi, TDn - test data, SIM...simulation results.

Claims (1)

[Claims] Means (1) for specifying an external terminal pin (Pi) of an integrated circuit and inputting corresponding test data (TDi) to the pin
and a display means (2) having a color display function, and when the corresponding test data (TDn) is input to any pin (Pn) specified by the data input means (1), the test data (TDn) is displayed. means (3) for executing a simulation for the pin; means (4) for comparing the simulation result (SIM) with a preset expected value corresponding to the pin (Pn); At that point, the simulation result (SIM) is displayed on the screen of the display means (2) in a predetermined color, and when the simulation result (SIM) does not match the expected value, the mismatch result is displayed in the predetermined color. A CA with a simulation function, comprising a display control means (5) for displaying a color in a different color.
D device.