US 4,831,524 A · Logic diagram compiler/executor

Abstract

The present invention is an interactive method of creating and executing a logic diagram. The designer can pick and connect logic elements using a menu. The diagram can be edited and tested using a generic logic element. As the diagram is being created, an equations list is produced. The equations list is converted into an executable format by producing a compressed version of the equations list which is loaded into an execution table one record at a time. Each record can cause plural equations to be loaded and the equations are linked via token pointers. The unrelated equations are linked through input and output pointers. Each intermediate file record can cause record locations for associated input and output tokens to be preassigned. When executing, an input is percolated through the equations until an impasse is encountered. If a branch shape is encountered, a token pointer for a different branch is pushed onto a stack. When an impasse is encountered, the token pointer on the stack is used to continue percolation. Whenever no token pointers remain on the stack and an impasse occurs, another input is brought into the execution table and percolated. When all return stack pointers and inputs have been executed, the system checks for incomplete logic states, assumes a value and continues percolation. When all incomplete states have been resolved, the system stops and the outputs can be used for actual control.

Claims27

Dependent claims

A method of creating and executing logic diagrams to produce device outputs from device inputs, comprising the steps, executed by a computer, of:

(a) designating a logic symbol shape and a location on a dynamic diagram for that shape;
(b) creating a logic equation for the shape;
(c) placing the shape in a token block on the dynamic diagram;
(d) repeating steps (a)-(c) until the dynamic diagram is complete;
and
(e) executing a logic diagram representing the dynamic diagram comprising the steps of:
(ei) creating execution equations from the logic equations;
and
(eii) retrieving the device inputs and executing the execution equations with the device inputs to produce the device outputs.

6 more elements

A method of creating and executing logic diagrams to produce device outputs from device inputs, comprising the steps, executed by a computer, of:

(a) designating a logic symbol shape and a location on a dynamic diagram for that shape;
(b) creating a logic equation for the shape;
(c) placing the shape in a token block on the dynamic diagram;
(d) repeating steps (a)-(c) until the dynamic diagram is complete;
and
(e) executing a logic diagram representing the dynamic diagram, step (e) comprising the steps of:
(ei) creating execution equations from the logic equations, step (ei) comprising the steps of:
(1) creating an intermediate file;
and
(2) loading the intermediate file into an execution table, step (2) comprising the steps of:
(1a) creating at least one execution table record for each intermediate file record;
(1b) preassigning input and output execution table records, as necessary, for the at least one execution table record and linking the preassigned records using input and output record pointers;
and
(1c) completing the input and output execution table records as a corresponding record in the intermediate file is encountered;
and
(eii) retrieving the device inputs and executing the execution equations with the device inputs to produce the device outputs.

13 more elements

A method of creating and executing logic diagrams to produce device outputs from device inputs, comprising the steps, executed by a computer, of:

(a) designating a logic symbol shape and a location on a dynamic diagram for that shape by designating a shape from a shape library and converting the location into a token block number;
(b) creating a logic equation for the shape by creating a dynamic equation list entry from a static equation definition, where the entry includes the token block number, an operation code, an output position indicator and input position indicators;
(c) placing the shape in a token block on the dynamic diagram by transferring the shape from the shape library to the dynamic diagram at the token block number indicated;
(d) repeating steps (a)-(c) until the dynamic diagram is complete;
and
(e) executing a logic diagram by creating execution equations from the logic equations and retrieving the device inputs and executing the execution equations with the device inputs to produce the device outputs, where executing the execution equations includes:
(1) propagating device inputs through equation table records until a multiple input execution table shape record is encountered;
(2) determining if all the inputs for the multiple input equation table shape record are available;
(3) processing the multiple input execution table shape record when all inputs are available;
(4) continuing propagation of the device inputs;
(5) pushing a token pointer onto a return stack when a multiple equation table record is encountered;
(6) continuing propagation of device inputs until an impasse is reached;
(7) continuing propagation with the equation table record corresponding to the token pointer;
(8) examining the execution table records for incomplete logic states when all inputs and impasses have been processed;
(9) assuming a value for an unavailable input for shapes with incomplete logic states;
and
(10) propagating the value through the equation table records.

14 more elements

A method of executing logic equations, comprising steps, executed by a computer, of:

(a) creating execution equations from the logic equations, step (a) comprising the steps of:
(1) creating an intermediate file;
and
(2) loading the intermediate file into an execution table, step (2) comprising the steps of:
(2a) creating at least one execution table record for each intermediate file record;
(2b) preassigning input and output execution table records, as necessary, for the at least one execution table record and linking the preassigned records using input and output record pointers;
and
(2c) completing the input and output execution table records as a corresponding record in the intermediate file is encountered;
and
(b) retrieving the device inputs and executing the execution equations with device inputs to produce device outputs.

7 more elements

Dependencies are inferred from the claim text.

Logic diagram compiler/executor

Life of this patent

Logic diagram compiler/executor

Life of this patent

Abstract

Claims27