JPH0512361A - Circuit diagram input device for logic circuit - Google Patents

Abstract

PURPOSE:To provide circuit diagram input device for the logic circuit which can easily select a desired logic element and also easily correct it into another logic element. CONSTITUTION:Many groups are defined for many logic elements. A group A is defined depending upon a difference in 'driving ability', a group B is defined depending upon a difference in 'the number of inputs', and a group C is defined depending upon a difference in 'logical output'. In each of the groups, the order of elements is defined. When an element (c) is newly selected while an element (a) is already selected, the group A showing the derivation of the difference in 'driving ability' is selected and an indication for selecting a next candidate is made twice. Thus, the new element can be selected by the method which deriving the characteristics of the currently selected element.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit diagram input device for a logic circuit, and more particularly to a circuit diagram input device for a logic circuit having a function of easily inputting a large number of logic elements.

[0002]

2. Description of the Related Art A circuit diagram input device for a logic circuit using a CAD device is used for designing a logic circuit or creating a logic circuit diagram. The operator is this CA
While looking at the display screen of the D device, an input device such as a keyboard or a mouse is operated to assign a symbol mark indicating a predetermined logic element to a predetermined position, and a predetermined wiring is provided between the respective logic elements.

In an actual circuit, a great variety of kinds of logic elements are used. For example, even if one basic logic element such as an AND circuit is taken, if the logic output is inverted, NAND
It becomes another logic element called a circuit and has two or three inputs.
If the number is different from four, they become different logic elements, and even if they have different drive capabilities, they become different logic elements. Therefore, in the conventional general circuit diagram input device of the logic circuit, these various kinds of logic elements are prepared in the form of a library, and the operator selects a necessary logic element from the library and selects the selected element. The work of arranging the symbol mark of is in a predetermined position.

[0004]

However, as the number of logic elements increases, the task of selecting a desired logic element from the library becomes more difficult. Normally, a means of displaying a list of the symbol marks of the logic elements prepared in the library on the menu screen on the display and selecting this with a mouse is adopted,
Searching for a desired element from a large number of logic elements is inefficient and error-prone. In addition, when performing a repair work to replace a specific logic element in the circuit diagram that was created once with another logic element, erase the already placed logic element, select a new logic element, and It is necessary to perform the work of relocating.

Therefore, an object of the present invention is to provide a circuit diagram input device of a logic circuit which can easily select a desired logic element and can easily modify another logic element. And

[0006]

According to the present invention, there is provided a circuit diagram input device for a logic circuit, wherein a symbol mark storage device storing a symbol mark used in a circuit diagram for a plurality of logic elements and a display device for displaying the symbol mark. A display device, an input device for inputting an instruction from an operator, and a plurality of logic elements satisfying the condition that one specific property is different from each other are defined, and a group having the collected logic elements as constituent members is defined, With respect to each group, a group information storage device that stores a logical element that is a constituent member and a rank of this logical element in the group,
An element selection device that selects one logic element from a plurality of logic elements based on an instruction from an operator, a selection element storage device that stores the logic element selected by this element selection device, and a selection element storage device The element placement device for arranging the symbol mark of the selected element stored in the display device at a predetermined position on the screen of the display device based on the instruction from the operator, and one group selected by the instruction from the operator are stored. A selection group storage device is provided, and a logic element defined in the next order of the logic elements stored in the selection element storage device with respect to the group stored in the selection group storage device is provided in the element selection device. , And has a function of selecting as a new selection element.

[0007]

[Operation] In the circuit diagram input device of the logic circuit of the present invention, the logic element to be assigned to the display device is stored in the selection element storage device. Then, the logic element to be stored in the selected element storage device is selected by the element selection device. Moreover, this element selection device uses, as a new selection element, the logic element defined in the next order of the logic elements stored in the selection element storage device with respect to the group stored in the selection group storage device. Has the function of selecting. Therefore, when an operator wants to select a desired logic element, he / she can specify a proper selection group and derive the current selection element into another logic element belonging to this selection group. It is possible to select various logic elements. Therefore, it is possible to easily select a desired logic element and also to easily modify another logic element.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on illustrated embodiments. FIG. 1 is a block diagram showing the basic configuration of a circuit diagram input device for a logic circuit according to the present invention. This device is made up of three major components: an input device 10, a computer 20, and a display device 30. The input device 10 is an input device for a general computer, such as a keyboard and a mouse, and functions to fetch an instruction from an operator into the computer 20. The display device 30 is a display device for a general computer, and has a function of displaying an image created by the computer 20. The center of the circuit diagram input device of this logic circuit is the computer 20, and the internal configuration is shown in a functional block diagram in the figure.

The function of each block constituting the computer 20 is as follows. Symbol mark storage device 21
Stores various types of symbol marks used in the circuit diagram, a group is defined for each logic element corresponding to the various types of symbol marks, and information about this group is stored in the group information storage device 22. There is. This group information will be described later in detail. The element selection device 23 uses the symbol mark storage device 21 based on an instruction given by the operator from the input device 10.
The selection element storage device 24 has a function of selecting one of the logic elements corresponding to the various kinds of symbol marks stored in the selection element storage device 24. The element placement device 25 reads the symbol mark corresponding to the selected element stored in the selected element storage device 24 from within the symbol mark storage device 21, and based on the instruction from the operator given from the input device 10, The read symbol mark is assigned to a predetermined position on the display screen of the display device 30. Further, the selected group storage device 26 stores a selected one of the groups defined in the group information storage device 22 based on an instruction from the operator given from the input device 10. The above is the configuration when the computer 20 is shown by functional blocks. In practice, each of these blocks will be implemented in computer hardware and software. For example, the symbol mark storage device 21 and the group information storage device 22 can be configured by the internal memory of the computer. Of course, these may be configured by an external storage device. A memory or a register may be used as the selection element storage device 24 and the selection group storage device 26. The element selection device 23 and the element placement device 25 are CPs of a computer.
It is realized by U and software that operates it.

The outline of the operation of this device is as follows. That is, the operator will perform the work of allocating a desired logic element on the display screen of the display device 30. First, the operator gives an instruction to the element selection device 23 to select the desired logic element. .. The selected logic element is stored in the selection element storage device 24. Subsequently, the operator gives an instruction to the element placement device 25 to indicate the allocation position of the selected element. Element placement device 2
5 recognizes the selected logic element from the stored contents of the selected element storage device 24, reads the symbol mark corresponding to it from the symbol mark storage device 21, and arranges it at the instructed allocation position. .. Thus, the logic element designated by the operator is arranged at the position designated by the operator.

The feature of this apparatus is the element selecting operation by the element selecting device 23. In order to explain this selection operation, first, the group information stored in the group information storage device 22 will be described. As aforementioned,
The symbol mark storage device 21 stores symbol marks for many kinds of logic elements. And
Several groups are defined for the various types of logic elements. That is, a plurality of logic elements satisfying the condition that one specific property is different from each other are collected, and a group in which the collected logic elements are constituent members is defined. FIG. 2 shows one group. This group is a group in which five logic elements having different "basic logic" are defined as constituent members. Inverter, NAND circuit, NOR circuit, EX-O from left to right
The R circuit and the flip-flop are logical elements, and both have different specific characteristics of “basic logic”. The group information storage device 22 stores, as group information, the logical elements that are constituent members and the in-group ranking of each logical element for the group defined in this way. For example, in the group shown in FIG. 2, these five logic elements are constituent members, and the fact that the ranks indicated by circled numbers in the figure are the ranks within the group is stored as group information. Note that the order here is what is called a rotation order, and is a cyclic order such as ,. That is, the next rank of is.

The group shown in FIG. 3 is "drive capability".
Is a group of which three logical elements having different specific properties are constituent members. X1, X2, X in the figure
Reference numeral 3 indicates the drive capability value of each logic element (in this specification, all logic elements whose drive capability value is not shown indicate the drive capability value X1).
Each of the three logic elements is an inverter element, but the three elements are different from each other in terms of the property of “drive ability”, and are ranked in order.
There are many groups other than the group shown in FIG. 3 that satisfy the condition that the property of “drive capacity” is different. For example, the group shown in FIG. 4 is also a group that focuses on the difference in the property of “drive capability”, but all of its constituent members are NAND circuits.

The groups shown in FIGS. 5 (a) and 5 (b) are groups satisfying the condition that the specific characteristics of "logical output" are different from each other. The constituent members of the group of FIG. 1A are NAND circuits and AND circuits,
The logic output is inverted. The constituent members of the group of FIG. 2B are a NOR circuit and an OR circuit,
After all, the logical output is inverted. On the other hand, the group shown in FIG. 6 is a group that satisfies the condition that the specific property of “the number of inputs” is different from each other, and the number of inputs 2,
The AND circuits of 3 and 4 are members. The group shown in FIG. 7 is also a group focusing on the difference in the property of "the number of inputs", but the constituent members are NAND circuits having 2, 3, and 4 inputs, and the "drive capacity" is Is also for "X3".

As described above, a large number of groups can be defined for a large number of logic elements. For example, as a group similar to the group shown in FIG.
It would be possible to define a collection of the numbers of inputs 2, 3, and 4 in the 2 "NAND circuit, and a similar group could be defined for the" X1 ". Further, it is also possible to define a plurality of groups for exactly the same logic element. For example, in FIG. 8, three groups A, B, and C are defined. Group A surrounded by a solid line has 2 inputs N
It is a collection of AND circuits, and is a group defined by focusing on the difference in "drive ability". On the other hand, the group B surrounded by the broken line is N of the drive capacity X1.
It is a collection of AND circuits, and is a group defined by focusing on the difference in "number of inputs". The group C surrounded by the alternate long and short dash line is a group of logical product circuits of the drive capability X1 and is a group defined by focusing on the difference in "logical output". When the three groups are defined in this way, the 2-input NAND circuit a having the drive capability X1 is
They will belong to all groups A, B, and C.

It is assumed that three groups A, B and C shown in FIG. 8 are defined in the group information storage device 22. More specifically, the members of each group, their rank, and the property of interest are stored as the following group information. In practice, it is preferable to define as many groups as possible in order to improve operability. 1. Group A: Focus on the difference in "driving ability". The constituent members are logic elements a, b, c, and a, b, c,
The rotation order of a, b, c, a, .... 2. Group B: Focus on the difference in "number of inputs". The constituent members are logic elements a, d, e, and a, d, e, a, d,
The rotation order of e, a, .... 3. Group C ... Focus on the difference in "logical output". The constituent members are logic elements a and f, and a, f, a, f, a,
The rotation order of f, a, ....

In the block diagram shown in FIG. 1, it is assumed that the logic element a shown in FIG. 8 is stored in the selection element storage device 24 as an initial setting. In this state, if the operator gives an instruction to the element placement device 25 to perform the assignment work, the logic element a can be assigned to any position. However, not the logic element a,
When allocating the logic element c whose "drive capacity" is X3, the operator may perform the following operation. First, for the selected group storage device 26, the work of designating the group A in order to derive the “drive capacity” is performed. Then, the device selection device 23 is instructed to select the next candidate. Then, the element selection device 23 selects the logic element b defined next to the logic element a stored in the selection element storage device 24 for the group A stored in the selection group storage device 26. Select as a new selection element. As a result, the selection element in the selection element storage device 24 is replaced with the logic element b. When the operator gives an instruction to select the next candidate, the selection element in the selection element storage device 24 is further replaced with the logic element c. Here, if an allocation instruction is given to the element placement device 25, the logic element c can be allocated.

Thus, after allocating the logic element c,
When allocating the logic element e this time, the following operation may be performed. First, in the state where the group A is designated as the selection group, the element selection device 23 is instructed to select the next candidate. Then, the selection element in the selection element storage device 24 returns to the logic element a again. Therefore, the work for designating the group B in order to derive the “number of inputs” is performed on the selected group storage device 26. Then, an instruction to select the next candidate is given to the element selection device 23 twice in a row. Then, the element selection device 23, with respect to the group B stored in the selected group storage device 26, the logic element d defined in the next order of the logic element a stored in the selection element storage device 24, and further The logic element e is selected as a new selection element. As a result, the selection element in the selection element storage device 24 is replaced with the logic element e. Here, if the allocation instruction is given to the element placement device 25, the logic element e can be allocated.

As described above, the operator can select a desired logic element while always deriving a selection element to obtain a new selection element. Therefore, the work of inputting the logic element becomes very easy. Particularly, in the device of this embodiment, the selected group storage device 26
When designating a selection group within, the selection group can be designated according to the particular property of interest. Specifically, "basic logic", "drive ability",
Display a heading of a specific property of “logical output” and “number of inputs” on a part of the display of the display device 30,
By designating one of these four headings with the mouse as the input device 10, the group corresponding to this is automatically designated. For example, when the group definition shown in FIG. 8 is made and the current selection element is the logic element a, the operator next selects the logic element c from which the “drive capability” is derived and assigns it to the desired position. Suppose you want to. At this time, the operator designates the heading "drive capability" on the display with the mouse (this sets group A in the selected group storage device 26), moves the mouse to a predetermined position, and then clicks the mouse button. Press twice (in the device of this embodiment, a mouse button gives an instruction to select the next candidate to the element selection device 23). Here, if an allocation instruction is given to the element placement device 25, the logic element c is allocated to the position designated by the mouse. In this way, regarding the currently selected element, it is possible to select a new element while deriving a specific property, so that the operability becomes very good.

Finally, the work of creating a logic circuit diagram by the present apparatus will be described by showing a more concrete example. Now, for example, consider the case where a circuit diagram as shown in FIG. 9 is created. Here, it is assumed that an inverter element is stored as a selection element in the selection element storage device 25 as an initial setting. In the circuit diagram shown in FIG. 9, 4 of I, J, K and L are used.
The logic element is arranged at each of the two positions. Therefore, first, the position I is designated by the mouse, and the allocation instruction is issued there. Since the initial selection element is the inverter element, the inverter element is assigned to the position I. Similarly, if the allocation instruction is given as it is at the positions J, K, and L, the inverter elements are allocated to all the positions, and the display screen of the display device 30 becomes as shown in FIG. With this, for the time being, a guide for the allocation positions for the four logic elements is obtained. Then, each logic element is replaced with a correct element. First, with the mouse, the heading "Basic logic" is designated, and group selection is performed so that the basic logic can be derived. Then, after deriving the inverter and selecting the NAND circuit, it may be assigned to the positions J and L. Finally, if a NOR circuit is selected and assigned to the position L, the circuit diagram shown in FIG. 9 can be created.

As described above, the element selection device 23 has a function of deciding a new selection element by deriving the selection element based on the rotation order with respect to a certain group, but in the apparatus of this embodiment, Besides this,
A function of setting the logic element displayed on the display screen as a new selection element in the selection element storage device 24 is provided. For example, consider a case where a circuit diagram as shown in FIG. 9 is displayed on the display screen. In this case, if the setting function is used with the position L specified by the mouse, the NOR circuit displayed at the position L can be set as a new selection element in the selection element storage device 24. Such a function is convenient for the work of modifying the circuit diagram. For example, consider the case where the circuit diagram shown in FIG. 9 is modified to the circuit diagram shown in FIG. In this case, the NOR circuit displayed at the position L is set as a new selection element by using the above-mentioned function with the position L specified by the mouse. Then, the heading "Logical output" is designated, and the heading shown in FIG.
By selecting the group D of No. 3 and giving an instruction to replace and correct the logic element of the next order in this group, the NOR circuit at the position L shown in FIG. 9 can be instantly replaced by the OR circuit (FIG. 12). Further, when the circuit diagram shown in FIG. 9 is modified to the circuit diagram shown in FIG. 14, the heading “Number of inputs” is designated, the group E in FIG. 13 is selected, and the next order within this group is selected. If the instruction to replace and correct the logic element is given, the 2-input NOR circuit at the position L can be instantaneously replaced by the 3-input NOR circuit.

In the above description, only the work of arranging the logic elements is described, but in practice, the work of instructing the wiring between the logic elements is required.

The present invention has been described above based on the illustrated embodiment, but the present invention is not limited to this embodiment and can be implemented in various modes other than this. In short, the present invention is based on a new method for inputting various kinds of logic elements, and by defining a group in advance and deriving the logic elements in a predetermined order within the group, a desired logic The feature is that elements can be selected. The present invention can be implemented in various forms without departing from this basic idea.

[0023]

As described above, according to the circuit diagram input device for a logic circuit according to the present invention, a group is defined for many kinds of logic elements, and the logic elements are derived in a predetermined order within this group. Since the desired logic element can be selected, the desired logic element can be easily selected, and the correction to another logic element can be easily performed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of a circuit diagram input device of a logic circuit according to the present invention.

FIG. 2 is a diagram showing an example of a group defined by focusing on a difference in property of “basic logic”.

FIG. 3 is a diagram showing an example of a group defined by focusing on a difference in property of “drive ability”.

FIG. 4 is a diagram showing another example of groups defined by focusing on the difference in the property of “drive ability”.

FIG. 5 is a diagram showing an example of a group defined by focusing on a difference in a property of “logical output”.

FIG. 6 is a diagram showing an example of groups defined by focusing on the difference in the property of “the number of inputs”.

FIG. 7 is a diagram showing another example of groups defined by focusing on the difference in the property of “the number of inputs”.

FIG. 8 is a diagram showing an example of a state in which a plurality of groups are defined in duplicate.

FIG. 9 is a diagram showing an example of a circuit diagram input by the device according to the present invention.

10 is a first operation for inputting the circuit diagram shown in FIG. 9. FIG.
It is a figure which shows a step.

FIG. 11 is a diagram showing another step of the operation for inputting the circuit diagram shown in FIG. 9;

12 is a diagram showing a state in which the circuit diagram shown in FIG. 9 is modified.

FIG. 13 is a diagram showing groups used for a work of correcting the circuit diagrams shown in FIGS. 12 and 14;

FIG. 14 is a diagram showing another state in which the circuit diagram shown in FIG. 9 is modified.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Input device (keyboard, mouse) 20 ... Computer 21 ... Symbol mark storage device 22 ... Group information storage device 23 ... Element selection device 24 ... Selection element storage device 25 ... Element placement device 26 ... Selection group storage device 30 ... Display device (Display device)

Claims (1)

Claims: 1. A plurality of logic elements, a symbol mark storage device storing symbol marks used in a circuit diagram, a display device for displaying the symbol marks, and an instruction from an operator is input. Input device and a plurality of logic elements satisfying the condition that a certain specific property is different from each other, define a group whose constituent members are the collected logic elements, and for each group,
A group information storage device that stores a logical element that is a constituent member and a rank of this logical element in a group, and an element that selects one logical element from a plurality of logical elements based on an instruction from an operator. A selection device, a selection element storage device that stores the logic element selected by the element selection device, and a symbol mark for the selection element stored in the selection element storage device, on the screen of the display device, the operator And a selection group storage device for storing one group selected by an operator's instruction, wherein the element selection device is the selection group storage device. For the group stored, the next rank of the logic element stored in the selected element storage device is set. Schematic capture device of the logic circuit logic elements that are characterized as having a function of selecting as the new selected element.