On-line modification of computer programs

• US 3,969,723 A
• Filed: 07/03/1974
• Issued: 07/13/1976
• Est. Priority Date: 07/03/1974
• Status: Expired due to Term

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Kennicott, Philip R.
• Primary Examiner(s): Zache, Raulfe B.
• Application Number:
  US05/485,766
• Time in Patent Office: 741 Days
• Field of Search: 340/172.5, 235/152
• US Class Current: 700/83
• CPC Class Codes: G05B 2219/13153 Modification, change of program in real time
• CPC Class Codes: G06F 8/656 while running

Abstract

A programmable data processor or controller serving as the main control in a control system contains an executive program for controlling the transfer of information between the processor and system equipment, updating that information during on-line control of the equipment and modifying the executive program to change operating parameters of the system while the data processor is controlling the system equipment. Modification of the executive program and displaying of system parameters related to the executive program and the system equipment is accomplished through the use of an operator'"'"'s console which communicates with the data processor and system equipment as a result of operator intervention.

Claims

1. In a controlled equipment system of the type operable in response to signals resulting from logical operations based upon operating parameters of the controlled equipment, a control system comprising:

a. a programmable controller including a store having stored therein an executive program serving to,

1. direct on-line communication between said controller and equipment external thereto, and

2. simulate an equipment control circuit having a format comprised of a plurality of logic strings, each logic string comprised of a conductor including at least one switch element disposed in a designated position and a continuity status means controlled by the condition of the switch elements of its associated logic string, said continuity status means serving to effect output signals from said controller to the equipment external thereto; and

,

b. a programming console in communication with said controller comprising;

1. means for specifying to said controller a one of the simulated logic strings to be modified,

2. means for directing said controller to copy the simulated specified logic string into a predetermined region in said store while retaining the specified logic string in the executive program,

3. means for specifying to said controller a position in the conductor of the logic string copied,

4. means for modifying the copied logic string by specifying to said controller a type of switch element,

5. means for directing said controller to test the modified logic string on-line as a part of the executive program in place of the retained specified logic string, and

6. means for directing said controller to replace the retained specified logic string with the modified logic string while maintaining the modified logic string on-line whereby the modified logic string becomes an integral part of the executive program to control the external equipment in accordance with the logic now defined by the modified logic string.

2. The invention in accordance with claim 1 wherein said programming console further includes means for specifying to said controller a location in said store of a condition referenced by the switch element at the specified position.

3. A controlled equipment system as recited in claim 1 wherein a plurality of types of switch elements may be specified to said controller by the means for modifying the copied logic string, said switch types comprising normally open and normally closed series and parallel switch contacts, said continuity status means comprises a relay coil and wherein said means for modifying a copied logic string comprises a plurality of switches mounted on said programming console, which switches are individually identified to correspond to a particular type of switch and relay coil.

4. A controlled equipment system as recited in claim 2 wherein said means for modifying a copied logic string further includes two switches mounted on said programming console, the first, when activated, deleting the switch element in the specified position of the specified logic string and the second, when activated, inserts a space creating a position in the specified logic string between two adjacent switch elements for the inclusion of an additional switch element.

5. In a controlled equipment system of the type operable in response to signals resulting from logical operations based upon operating parameters of the equipment, a control system comprising:

a. a programmable controller including a store having stored therein an executive program serving to,

1. direct on-line communications between said controller and equipment external thereto,

2. simulate an equipment control circuit having a format comprised of a plurality of logic strings, each logic string comprised of a conductor including at least one switch element disposed in a designated position and a continuity status means controlled by the condition of the switch elements of its associated logic string, said continuity status means serving to effect output signals from said controller to the equipment external thereto; and

,

b. a programming console in communication with said controller comprising,

1. means for selectively specifying to said controller simulated logic strings to be modified,

2. manually operable copy means for directing said controller to copy a selected simulated logic string into a predetermined region in said store each time said copy means is operated while retaining all such logic strings in the executive program,

3. means for specifying to said controller the identity of a logic string copied and a position in the conductor of that copied logic string,

4. means for modifying the selected copied logic string by specifying to said controller one type of a plurality of types of switch elements to change the type of switch element at the specified position,

5. means for directing said controller to test all copied logic strings on line as a part of the executive program in place of the retained specified logic strings, and

6. means for directing said controller to replace the retained specified logic strings with their corresponding copied logic strings while maintaining the copied logic strings on-line whereby the copied logic strings become a permanent part of the executive program to control the external equipment in accordance with the logic now defined by the copied logic strings.

6. A control system for controlling equipment of the type operable in response to signals resulting from logical operations performed by a portion of an equipment control circuit, said system comprising:

a. a programmable controller including a store having stored therein an executive program for directing communication between said controller and equipment external thereto, said executive program further simulating an equipment control circuit having a format comprising a plurality of logic strings, each logic string comprised of a conductor including a plurality of positions for the inclusion of one type of a plurality of types of switch elements, the conditions of which determine the status of continuity of the conductor, and each of said conductors further including a continuity status means controlled in accordance with the continuity of its associated conductor, said continuity status means serving to control output signals from said controller to said external equipment;

5. a programming console in communication with said controller comprising,

1. means for specifying to said controller a one of said logic strings,

7. means for directing said controller to copy the specified simulated logic string into a predetermined region in said store while retaining the specified logic string in the executive program,means for specifying to said controller a position in the conductor of the logic string copied,means for modifying the copied logic string by specifying to said controller one type of the plurality of types of switch elements to change the type of switch element at the specified position,means for specifying to the controller the location in store of a condition referenced by the switch element at the specified position,means for specifying to said controller to test the modified logic string on-line as part of the executive program in place of the retained specified logic string, andmeans for specifying to said controller to replace the retained specified logic string with the modified logic string whereby the modified logic string becomes a permanent part of the executive program to control the external equipment in accordance with the logic now defined by the modified logic string.

9. The invention in accordance with claim 7 wherein said console further includes means for specifying to said controller that the program is to effect the allocation of additional store locations for receiving the electrical control circuit information from the specified store locations.

8. A system for controlling process equipment of the type having electrical devices which respond to electrical control signals selectively provided to said electrical devices, said system comprising:

a. a programmable controller in communication with said process equipment, said controller including a store having an executive program stored therein for selectively controlling the transfer of signals between said controller and said process equipment for the control thereof, said program simulating an electrical control circuit having a format comprising a plurality of logic strings, each of said logic strings including a plurality of logic elements in specified positions thereof and each logic element representing one logic condition of a plurality of logic conditions, the outputs of said logic strings serving to provide said electrical control signals; and

,

b. an operator'"'"'s console in communication with said programmable controller for programming simulated electrical control circuit information into the store of said controller, said operator'"'"'s console comprising,

1. selection means for designating to said controller one of said plurality of logic strings, the position of one of said plurality of logic elements in the one designated string, and the logic condition of that designated logic element,

2. means for specifying to said controller to copy from the program the designated logic string and all of the logic elements in that one designated string as data into specified store locations without altering the executive program,

3. means for specifying to said controller that the data in the specified store locations is to be selectively altered as designated by said selection means,

4. means for specifying to said controller to effect the testing of altered data in the specified store locations by causing the executive program to recognize the altered data as a part of the program, and

5. means for specifying to said controller to transfer the altered data from said specified store locations into said executive program to substitute the data previously copied from said program into the specified store locations.

10. A system for controlling process equipment of the type having electrical devices which respond to electrical control signals selectively provided to said electrical devices, said system comprising:

a. a programmable controller in communication with said process equipment, said controller including a store having an executive program stored therein for selectively controlling the transfer of signals between said controller and said process equipment, said program simulating an electrical control circuit for the production of said electrical control signals having a format comprising a plurality of logic strings, each of said logic strings including a plurality of logic elements in specified positions thereof and each logic element representing one logic condition of a plurality of logic conditions;

b. an operator'"'"'s console in communication with said programmable controller for programming simulated electrical control circuit information into the store of said controller, said operator'"'"'s console comprising,

1. selection means for designating to said controller one of said plurality of logic strings, the position of one of said plurality of logic elements in the one designated string, and the logic condition of that designated logic element,

2. means for specifying to said controller to copy from the program the one designated plurality of logic strings and all of the logic elements in that one designated string as data into specified store locations without altering the executive program,

3. means for specifying to said controller in a first instance that the data in the specified store locations is to be selectively altered as designated by said selected means, and specifying in a second instance that electrical control circuit information for entry into the program is to be stored into certain ones of the specified store location as designated by the selection means,

4. means for specifying to said controller that the program is to effect the allocation of store locations for receiving altered data and the electrical control circuit information from the specified store locations,

5. means for specifying to said controller to effect the testing of the altered data and the electrical control circuit information in the specified store locations by causing the executive program to recognize the altered data and the control circuit information as a part of the program, and

6. means for specifying to said controller to transfer the altered data and the control circuit information from said specified store locations into said executive program and into the additional store locations allocated by the program whereby the altered data and the electrical control circuit information form a part of the program; and

,

c. means for effecting the running of said executive program whereby said electrical control signals are produced.

11. A programming console for selectively communicating information to a programmable controller, the controller having stored therein a program representative of a control circuit in electrical diagram form, the electrical diagram having a format comprising a plurality of strings of logic elements contained in specified positions in said strings, each logic element being in the form of an instruction word, certain ones of the instruction words in each logic string specifying one type of a plurality of logic functions to be performed and at least one other instruction word in each logic string referencing a logic condition which it is to control the condition of said programming console comprising:

a. means for selecting a string of logic elements of the control circuit in which the logic function of a logic element is to be changed;

b. a keyboard comprising individual keys, each key, when activated selecting one type of the plurality of types of logic elements;

c. means for displaying the type of logic element selected and the position of the logic element in the selected string of logic elements;

d. means for testing the operation of the selected information transmitted to said programmable controller prior to changing the selected information in the program; and

,

e. means for entering the selected information into the program to effect a change therein in the selected logic element of the selected logic string.

12. A programming console for a programmable controller, said controller including a memory having stored therein a program for communicating with said console and simulating a control circuit in ladder diagram format, the ladder diagram format comprising a plurality of logic strings, each ligic string comprised of a conductor including at least one switch element in a designated position therein and a continuity status means controlled by the condition of the switch elements of its associated logic string, said programming console comprising:

a. selection means for specifying to said controller a one of the simulated logic strings;

b. copy means for directing said controller to copy the simulated selected logic string into a copy region of said memory while retaining the selected logic string in the program;

c. means for specifying to said controller a position in the conductor of the logic string copied;

d. means for modifying the copied logic string by specifying to said controller one type of a plurality of types of switch elements to change the type of switch element at the specified position;

e. means for directing said controller to test the modified logic string as a part of the program in place of the retained specified logic string; and

,

f. means for directing said controller to replace the retained specified logic string with the modified logic string while the program continues to execute the modified logic string whereby the modified logic string becomes a permanent part of the program as defined by the modified logic.

13. A programming console for a programmable controller, said controller including a memory having stored therein a program for communicating with said console and a replica of a control circuit in ladder diagram format, the ladder diagram format comprising a plurality of circuit conductors having position, each position capable of including one type of a plurality of logic functions, some of which perform logical operations and others which perform no operations, said programming console comprising:

a. selection means for selecting a circuit conductor of the control circuit which is to be modified;

b. copy means for specifying to said controller to make a copy of the conductor of the control circuit selected by said selection means to a copy region of said store for the modification thereof;

c. means for selecting one of the positions in the copied conductor into which a logic function is to be placed;

d. means for selecting one type of the plurality of types of logic functions for placement in the selected position of the copied conductor;

e. means for specifying to said controller to test the modified copied conductor as a part of the control circuit in place of the originally selected circuit conductor; and

,

f. means for entering the test copied conductor into the originally selected circuit conductor, said copied conductor replacing the originally selected conductor to form a modified control circuit.

15. The method as provided in claim 13 wherein the modifying of the copied logic string is accomplished by specifying which of several types of simulated switch elements including normally open and normally closed, series and parallel types are to be placed into the specified location.

16. The method as provided in claim 13 in which the modifications are achieved under operator control by the selected setting of manual operating elements.

14. A method of providing modification to a program located within a store of a data processing system including a programmable controller comprising the steps:

a. storing a program within said store, said program including first and second portions respectively, to

1. direct on-line communication between said controller and equipment external thereto, and

2. simulate an equipment control circuit having a format comprised of a plurality of logic strings, each logic string comprised of a conductor including at least one switch element disposed in a designated position and a continuity status means controlled by the condition of the switch elements of its associated logic string, said continuity status means serving to effect output signals from said controller to the equipment external thereto; and

,

b. effecting the modification of the second portion of said program through the use of an operator console by

1. specifying a one of the simulated logic strings to be modified,

2. copying the specified simulated logic string into a predetermined region in said store while retaining the specified logic string in the first portion,

3. specifying a position in the conductor of the logic string copied,

4. modifying the copied logic string by specifying a type of switch element,

5. testing the modified logic string on-line as a part of the program in place of the retained specified logic string, and

6. replacing the retained specified logic string with the modified logic string while maintaining the modified logic string on-line whereby the modified logic string becomes a integral part of the program to control the external equipment in accordance with the logic now defined by the modified logic string.