JPH0363878A - Lsi design supporting system - Google Patents

Abstract

PURPOSE:To easily design a large scale and complicated circuit in a short time by providing a graphic conversion means to automatically generate a state transition table from a state transition chart or to automatically generate the state transition chart from the state transition table. CONSTITUTION:The state transition chart representing transition relation between the states of a circuit is generated from graphic input with a state transition chart generating means 1, or the state transition table is generated by inputting state transition data representing a transition condition between the states of the circuit with a state transition table generating means 2. And the state transition table is automatically converted from the state transition chart or the state transition chart from the state transition table with a graphic conversion means 3, and also, a circuit diagram or description representing an operation in a state is generated with an in-state circuit generating means 4. In such a way, it is possible to facilitate the functional design of an LSI, and to shorten a design period.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an LSI design support system that performs the design of a circuit including a state system using in-house input in the functional design of an LSI.

(Prior Art) Conventionally, circuit diagram input systems for designing LSI functions have been limited to designing statically operating circuits. However, in-membrane circuit design can be roughly divided into static circuit operation design and state transition system design in which the operation order is determined and the operating state is controlled. Therefore, if you try to express a state system using the circuit diagram input system, you must newly install a flip-flop in the circuit for state assignment, and use the state signal to this flip-flop as a control signal to operate the circuit. This, of course, requires a large number of flip-flops, which poses a problem in that the input circuit becomes large-scale and complex.

On the other hand, methods for representing state systems (sequential circuits) include Moof-type representation (output is determined only by the state) and Mier-type representation (output is determined by state and input).For example,
In the Mirri-type representation, a state transition diagram is used to express as shown in FIG.

In this case, if 1 is input in state qO, state Q
This indicates that the signal transitions to + and outputs 1. Also,
This can be expressed using a state transition table as shown in FIG. 10, and vice versa.

Therefore, with the aim of applying this concept to the design of logic circuits, graphical input systems for state transition diagrams or state transition tables have been considered.

However, in such a conventional system,
There was a problem in that the connections were complicated because the design was done independently of the static circuit operation. In addition, it is necessary to completely define transition conditions etc. before designing.
There was a problem in that it was not possible to design flexibly by adding or changing state transition conditions during circuit design.

(Problems to be Solved by the Invention) As mentioned above, in conventional LSI design support systems in which all circuit operations are designed by inputting circuit diagrams, the circuit diagrams input when expressing the circuit state are large-scale. , there was a problem that the design work became complicated and the design work could not be carried out smoothly.

In addition, when designing circuit operations and state transition systems, the state transition diagram or state transition table is designed separately from the circuit operation part, and the circuit diagram, state transition diagram, and state transition table are used. It is not done in parallel,
The design range was narrow, and it was not possible to design a circuit that focused on the state of the circuit and understood the circuit operation in each state.

Furthermore, in conventional systems, there is a problem in that it is not possible to proceed with the design if conditions such as state transition conditions are uncertain.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide an LSI design support system that facilitates the functional design of LSI and shortens the design period.

[Structure of the Invention] (Means for Solving the Problems) The LSI design support system according to claim 1 of the present invention includes state transition diagram creation means for creating a state transition diagram showing transition relationships between states of a circuit by inputting a graphic. or state transition table creation means for creating a state transition table indicating transition conditions between transitionable states of the circuit by inputting state transition data;
Intra-state circuit creation for creating a circuit diagram or description representing an operation within a state in a state transition diagram created by the state transition diagram creation means or a state transition table created by the state transition table creation means by graphical input or descriptive input. a means for converting a state transition diagram created by the state transition diagram creation means into a state transition table, or converting a state transition table created by the state transition table creation means into a state transition diagram; A state transition diagram created by a transition diagram creation means, a state transition table created by a state transition table creation means, a state transition table from a state transition diagram transformed by the shape conversion means; a state transition diagram from a converted figure or a state transition table; The apparatus includes a display means for displaying at least one of a conversion figure and a state-in-state operational circuit diagram or description created by the state-based circuit creation means.

The LSI design support system according to claim 2 of the present invention includes a state transition diagram creating means for creating a state transition diagram showing a transition relationship between states of a circuit by inputting a graphic, and a state transition diagram created by the state transition diagram creating means. a state transition table creation means for creating a table showing transition conditions between transitionable states in the diagram, and a circuit diagram or description representing the operation within the state in the state ai transition diagram created by the state transition diagram creation means In-state circuit creation means created by input or descriptive input, in which the function of the circuit is expressed separately for each state of circuit operation, and the part that operates within a certain state is compared with another state. A state transition diagram created by the state transition diagram creation means, a state transition table created by the state transition table creation means, and and display means for displaying the state-based circuit diagram or description created by the state-based circuit creation means.

(Function) In the LSI design support system according to claim 1 of the present invention, the state transition diagram creating means creates a state transition diagram showing the transition relationship between the states of the circuit from the graphic input, or the state transition table creating means creates the state transition diagram of the circuit. A state transition table is created by inputting state transition data indicating transition conditions between states.

Then, the figure conversion means automatically converts and creates a state transition table from the state transition diagram created by the state transition diagram creation means, or a state transition diagram from the state transition table created by the state transition table creation means. do.

Further, a circuit diagram or description representing the operation within the state in the state transition diagram or state transition table is created by the state circuit creation means.

The state transition diagram, state transition table, and in-state circuit diagram or description obtained in this way can be displayed by a display means and used for circuit design work by a designer.

In the LSI design support system according to claim 2 of the present invention, the state transition diagram creating means creates a state transition diagram showing transition relationships between states of the circuit, and the state transition table creating means creates transitionable states in the state transition diagram. Create a state transition table that shows the transition conditions between. Further, the state circuit creation means creates a circuit diagram or description representing the operation within the state in the state transition diagram created by the state transition diagram creation means from the graphic input or description input, and furthermore, the state circuit creation means creates a circuit diagram or description representing the operation within the state in the state transition diagram created by the state transition diagram creation means. In this section, parts that operate in a certain state of interest, parts that operate in another state to be compared with this state, and parts other than these are distinguished and expressed.

The state transition diagram created in this way by the state transition diagram creation means, the state transition table created by the state transition table creation means, and the in-state operation circuit diagram or description created by the state circuit creation means are displayed by the display means. and use it for LSI circuit design work.

(Example) Hereinafter, embodiments of the present invention will be explained in detail based on the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment in which the LSI design support system according to claims 1 and 2 of the present invention is implemented simultaneously, and FIG. 2 is a display means displayed by the system shown in FIG. 1. FIG. This example displays a state transition diagram, a state B transition table, and an in-state operation circuit diagram simultaneously in a multi-window format, making it easy to use a simple CP.
This is for when designing the functions of U.

In FIG. 1, the LSI design support system includes a state transition diagram creation section 1, a state transition table creation section 2, and a figure conversion section 3.
, and a state internal operation circuit creation section 4.

The state transition diagram creation unit 1 is an editor that creates a state transition diagram by inputting transition relationships between a plurality of states in a function according to the specifications of an LSI to be designed. State Transition Diagram
am) is created as shown in the upper left of FIG. 2, for example. The state transition diagram shown in FIG. 2 shows the state transition relationship in the operation of the CPU.

The state transition table creation unit 2 creates an LSI to be designed.
This is an editor that creates a state transition table by inputting transition conditions between multiple states in a function according to the specifications.

State Transition Table
ion Table) is created, for example, as shown in the lower left of FIG. In addition, the state transition table creation unit 2 has various editing functions prepared as menus.
Changes and amendments to conditions, etc. will be made. That is, editing operations such as adding, suppressing, and deleting condition signals, condition values, etc. are performed in an interactive manner using such editing functions. Further, the state transition table creation unit 2 has a function of searching for states that can be transitioned to the currently designed state using previously created tables and displaying the results in a table on the screen.

The graphic conversion unit 3 is a part that automatically converts a state transition diagram into a state transition table, or a state transition table into a state transition diagram. The state transition diagram shown in Figure 9 and the state shown in Figure 10! ! ! Transition tables are originally just data input representations that have been changed, so they essentially represent the same thing, and the designer can decide which design is better depending on his or her preferences and design purpose. In order to be able to arbitrarily select the
The state transition diagram created in the state transition table creation section 2 is converted into a state transition table, and conversely, the state transition table created in the state transition table creation section 2 is transformed into a state transition diagram.

The in-state operation circuit creation unit 4 is the state transition table creation unit 2.
This is an editor that creates in-state operating circuits or descriptions representing the operation of circuits in each state created by graphic input or descriptive input. The circuit diagram or description in language created by the in-state circuit creation section 4 is as shown on the right side of FIG. 2. The circuit diagram or description displayed on this screen includes not only the operating circuit within each state, but also the state name 5TSTOR currently designed in the upper left corner of the circuit diagram display area, and the states that can be transitioned before and after this state. (Previous state: 5TREAD.

5TFTCH, state after: 5TLAST, 5TEND,
5TFTCH) is displayed. In addition, the in-state operation circuit diagram is the same as the state transition table, as shown in Figure 2.
The circuit operation within the state STOR is shown by a thick solid line, the state before the 5TSTOR state is shown by a dotted line, and other parts are shown by thin solid lines so that they can be distinguished.

Note that the identification display can also be done by color coding or other methods.

The initial setting section 5 sets initial parameters for a state transition diagram, a state transition table, and an intra-state operation circuit created by inputting from each input section.

The database 6 includes the input section and initial setting section 5 described above.
Stores the data input by. The data in this database 6 is outputted via a data output section 9 controlled by an input control section 7 and an output control section 8.

As shown in FIG. 3, the data person output section 9 includes a data input display section 91 for inputting and displaying design data, and a display section 92 for displaying output. The data input display section 91 is composed of a graphic input section/display layer 911 that inputs and displays graphics, and a language input section/display layer 912 that inputs and displays languages. They can be displayed simultaneously. Both of these graphic inputs and language inputs are immediately converted and stored in the database 6 by a graphic/language integrated processor 71 corresponding to the input control section 7 shown in FIG.

Next, the operation of the LSI design support system having the above configuration will be explained.

As shown in the design flowchart shown in Figure 4, when designing a circuit, first consider a module that performs a specific operation, such as a finite state machine such as a CPU, and then design a large data flow between modules on a state transition diagram. do.

Next, state transitions are designed for each module using a state transition diagram or a state transition table (steps S3, 3
2).

Considering the system clock, design the internal operation for each state symbol. In this case, when the symbol of the state to be designed is selected with the mouse, an editor for creating a state transition table or an internal operation circuit is opened. In addition, in the case of a polyphase tally, φ1. φ2. φ3.・
...Create internal operations for each sheet. A clock that does not specify anything in particular for this internal operation is treated as a system clock. When the operation within the state is created using a circuit diagram, it is created using functional blocks such as ALU and REG (step S3).

During design, the signal names used in state transitions and circuit diagrams are checked through a check program for undefined items and for inconsistencies in transition relationships, and then stored in a database (steps S4 and S5). .

Next, using the data in the database thus obtained, a functional description is created by extracting state transition relationships and circuit operations using a functional description conversion program.

This description is used as input data to functional simulators, logic synthesis, and functional test generation systems.

In the state transition diagram creation step described above, the designer first inputs possible states in the circuit to be designed from the state transition diagram creation section 1 and creates a state transition diagram while looking at the screen display. For example, when designing the functionality of a CPU,
A state transition diagram STD as shown in the upper left of FIG. 2 is created. The states of the CPU as shown in FIG.
OR) etc. are displayed on the screen as you input them.

In addition, the transition relationship between each state is expressed by an arrow input to each state and an arrow output from each state, and the currently designed state (STS
TOR), its status is displayed surrounded by a thick line frame.

At the same time as the state transition diagram creation section 1 creates the state transition diagram, the graphic conversion section 3 automatically creates a state transition table STT, and for the state currently being designed (STSTOR),
The screen is displayed as shown in the lower left of FIG.

The detailed operation of this figure converter 3 will be explained based on FIGS. 5 and 6. The figure conversion section 3 has a common structure with a transition condition analysis section 10 that analyzes transition conditions for the state transition diagram 81 from the state transition diagram creation section 1 or the state transition table B2 from the state transition table creation section 2. An automatic placement and wiring program execution unit 11 that creates a state transition diagram from state transition table data stored in the database 6; and an automatic table creation program execution unit 12 that creates a state transition table from the state transition diagram data stored in the database 6. It is made up of.

In the state transition diagram 81, state symbols are connected with transition condition labels, and when unconnected, the transition conditions and transition destination states are written as labels on the output side of the state symbols.

The transition condition analysis unit 10 extracts transition condition signal names, signal values, and transition destination state names from the data input from the state transition diagram or state transition table editing screen, classifies and organizes them by condition signal name, and commonizes them. The information is stored in the database 6 of . For example, if input is from a state transition diagram as shown in FIG. 6(a), it can be seen that S is true. That is, it is sufficient to extract A and B as state transition condition signals. As a transition condition, all cases can be expressed by the value of a signal obtained by concatenating the bits of signal A and signal B (expressed as A!j13, for example).

Here, first, under the condition A=■, the state transition (s
tl→5t2). During this transition process, signal B can have any value. In this case signal B
is a don't care (for example, if it is represented by the symbol "?", this condition can be expressed as A!!B-'s?). Also, the condition for transitioning from state stl to state st3 is that A! ! B-10
becomes. These analysis results are temporarily stored in a common database 6. The data extracted from this common database 6 and expressed in the form of a state transition table is shown in Figure 6 (b). Even if
is converted into a state transition diagram through Note that similar analysis is performed when nested conditions are expressed as in the state transition table of FIG.

The automatic placement and wiring program execution unit 11 extracts transition conditions and transition relationships from the common database 6, places state symbols on the state transition diagram editor, attaches the transition conditions as labels, and automatically wires them to create a state transition diagram 81. do.

The automatic table creation program execution unit 12 extracts data from a common database 6 organized by condition and automatically creates the state transition table B2.

The state transition table STT in FIG. 2 can also be created by inputting state transition conditions and a transition destination state name for the state currently being designed in the state transition table creating section 2. When inputting this state transition table data,
The names and values of the condition signals to be input do not need to be specifically defined. Until the transition conditions are finalized, it is also possible to input a string of characters that indicates the conditions under which the conditions are met for reference. Also, as a state transition condition signal, you can use the name of the state to transition to and set it like "NEXT-STFTCH".This means that the next state to transition to is 5TPTCH.
, the signal is treated as having a value of "1". Similarly, "PREV-5TFTCH" is expressed as a signal that becomes "1" when the state before transition to the current state is 5TPTCH.

Therefore, in the state transition table of FIG. 2, the condition signal C1
is “NEXT-3TFTCH”, this condition signal C
Enter 5TPTCH in the transition destination state column in the left column where 1 is entered, and if the condition signal C1 is other than that (others), enter an arrow.

When this arrow is clicked with the mouse, the transition destination state input mode is entered, and a table of transition conditions and transition destination states regarding the nested second condition is newly displayed in a pop-up menu format on the right side. A condition signal G serving as this second condition is written, and this condition signal G becomes "
0”, the transition destination state is 5TEND, and the state is “1”.
”, the transition destination state is 5TLAST (this is)
(ready state waiting for sex).

In the in-state operation circuit creating section 4, by selecting which state's behavior is to be designed on the state transition diagram or state transition table as shown in FIG. 7 (step 511), the behavior design screen for that state is displayed. The operating circuit or description is created, and there are two ways to input this design.
The first case is when inputting a new circuit (step 513).
), and the other is to select the operating part in this state from among the circuits that have already been input (step 514).
.

When inputting a new circuit, as shown in FIG. 8, first select a functional block to be input from the library Bll of the database 6 (step 5131), place the selected functional blocks respectively (step 5132), and then add wiring or Perform signal naming (step 3133)
.

The circuit diagram data input in this way is stored in the database 6.
It is saved in the overall diagram data area B12, and pointers of each instance and connection are saved in the operation part table 813 in this state.

In addition, in step S14 of FIG. 7, when selecting from among the circuits that have already been input, the in-state operation part data 8 of the part displayed as the operating part in another state.
13 as the active part in this state, pointers to instances and connections of that circuit part are saved in the active part table in this state.

If the state currently being designed is 5TSTOR in the state transition diagram as shown in FIG. 2, the intra-state operating circuit creating section 4 creates an intra-state operating circuit diagram FD as shown on the right side of the figure. and display it. In this screen display, parts that operate in the 5TSTOR state under design are displayed with thick solid lines, circuit diagrams that can transition to this 5TSTOR state and have already been designed are displayed with broken lines, and other parts are shown with thin solid lines. are distinguished and displayed.

For example, if you are in a state where you can transition to the 5TSTOR state,
Register A1 Register R shown in FIG.

Assuming that parts of register C and memory M have already been designed, these are shown with dashed lines.

In such a state, when designing a 5TSTOR state, these circuit diagrams are referred to and the data given from register R to memory M is stored in memory M at the address given from register C to memory M. A 5TSTOR state is designed, and as shown in FIG. 2, registers R1, register C, and memory M are displayed as thick solid lines on the screen. Then, correction operations such as insertion, deletion, and movement of in-state working circuit data can be performed on the portion displayed by the thick solid line.

Also on this circuit diagram, the "PREV-" and "NEXT"
-” signal can be set directly.Also, if you place the condition symbol C1 at the location where the state transition branches depending on the condition and click this symbol with the mouse, the symbol F
The output value and the name of the transition destination state at that time are displayed as a list for each part that has been designed. This works similarly for conditional symbols or data branch positions.

In the case of a multiphase tarlock, the state transition table and the in-state operation circuit diagram are adjusted for each clock phase.

In this way, the functional design of the LSI is advanced by repeatedly performing the input creation and modification operations of the state transition diagram, state transition table, and in-state operation circuit diagram as appropriate. Since we design LSIs by dividing each LSI function and displaying them simultaneously on a single screen,
It becomes possible to provide a design environment that focuses on the state of the circuit, and it becomes possible to easily design even large-scale and complex circuits in a short period of time.

[Effects of the Invention] As described above, according to the invention of the LSI design support system of claim 1, the state transition table is automatically created from the state transition diagram created by the state transition diagram creation means, or the state transition table is created. Since it is equipped with a figure conversion means that automatically creates a state transition diagram from the state transition table created by the means, the designer inputs the state transition conditions and converts the state transition diagram data or form 7! ! A state transition diagram and a state transition table can be automatically created by simply inputting either one of the transition table data, and various input methods are available.

Further, according to the invention of the LSI design support system of claim 2, the in-state operating circuit creation means generates an operating circuit in a state of interest, an operating circuit in another state to be compared with the operating circuit in this state, and Since the circuits are displayed in a format that allows them to be distinguished from each other, circuits operating within a state can be designed by comparing them with operating circuits in other states, making the design work more efficient.

[Brief explanation of drawings]

FIG. 1 is a circuit block diagram of an embodiment of the present invention, FIG. 2 is an explanatory diagram showing the multi-window display state of the display section in the above embodiment, and FIG. 3 is a diagram of the data input/output section in the above embodiment. FIG. 4 is a block diagram showing the detailed configuration, FIG. 4 is a flowchart explaining the LSI design procedure according to the above embodiment, FIG. 5 is a block diagram showing the detailed groove bottom of the figure conversion section in the above embodiment, and FIG. An explanatory diagram showing a state transition diagram-state transition table conversion figure by the above-mentioned figure conversion section, FIG. 7 is a flowchart explaining the operation of the intra-state operation circuit creation section in the above embodiment, and FIG. FIG. 9 is an explanatory diagram showing a row of a general state transition diagram, and FIG. 10 is an explanatory diagram showing an example of a general state transition table. be. 1... State transition diagram creation section 2... State transition table creation section 3... Graphic conversion section 4... In-state operation circuit creation section 5... Initial setting section 6... Database 7...
・Input control section 8... Output control section 9... Data input/output section 3-circuit conversion section Fig. 1

Claims (2)

[Claims] (1) A state transition diagram creation means that creates a state transition diagram showing transition relationships between states of a circuit by inputting graphics, or creating a state transition table showing transition conditions between possible states of a circuit by inputting state transition data. a state transition table creation means for creating a state transition table; a state transition diagram created by the state transition diagram creation means;
or an in-state circuit creation means for creating a circuit diagram or a description representing an operation within a state in a state transition table created by the state transition table creation means by graphic input or description input; and a state created by the state transition diagram creation means. a figure conversion means for converting a transition diagram into a state transition table or converting a state transition table created by the state transition table creation means into a state transition diagram; and a state transition diagram or state transition created by the state transition diagram creation means. The state transition table created by the table creation means,
A state transition table conversion figure from the state transition diagram created by the figure conversion means or a state transition diagram conversion figure from the state transition table, and a circuit diagram or description representing the operation within the state created by the in-state circuit creation means. an LSI design support system comprising: display means for displaying at least one of the following. (2) A state transition diagram creating means for creating a state transition diagram showing transition relationships between states of a circuit by inputting a graphic, and transition conditions between possible states in the state transition diagram created by the state transition diagram creating means. state transition table creation means for creating a table showing the state transition diagram; and in-state circuit creation for creating a circuit diagram or description representing the operation within the state in the state transition diagram created by the state transition diagram creation means by graphical input or descriptive input. It is a method that expresses the function of a circuit by dividing it into each state of the circuit's operation, and distinguishes between a part that operates in a certain state, a part that operates in another state to be compared with that state, and a part that operates in another state to be compared with that state. A state transition diagram created by the state transition diagram creation means, a state transition table created by the state transition table creation means, and an in-state operation created by the in-state circuit creation means. 1. An LSI design support system comprising display means for displaying at least one of a circuit diagram or a description representing.