Remote diagnostic apparatus

• US 3,958,111 A
• Filed: 03/20/1975
• Issued: 05/18/1976
• Est. Priority Date: 03/20/1975
• Status: Expired due to Term

• Current Assignee: Bell Telephone Laboratories, Inc. (Nokia Corporation)
• Original Assignee: Bell Telephone Laboratories, Inc. (Nokia Corporation)
• Inventors: Hackett, John Arthur
• Primary Examiner(s): Atkinson, Charles E.
• Application Number:
  US05/560,316
• Time in Patent Office: 425 Days
• Field of Search: 235/153 AK, 235/153 AC, 235/153 AE, 340/146.1 BE, 340/172.5, 179/175.2 R, 179/175.2 C
• US Class Current: 714/31
• CPC Class Codes: G06F 11/2294 by remote test
• CPC Class Codes: H04Q 3/54558 Redundancy, stand-by

Abstract

A diagnostic controller is situated with a pair of duplicated logic units which themselves are remotely situated in relation to a controlling data processing unit. A distinct data path is provided between each of the remote logic units and the data processing unit for the conveyance of control information therebetween. When a remote logic unit appears to malfunction, the data processing unit takes the associated data path out-of-service and transmits commands over the in-service data path to start the diagnostic controller. Responsive to these commands, the diagnostic controller autonomously simulates data received over the out-of-service data path and applies the simulated data to the suspect remote logic unit. Results from this suspect unit are compared by the diagnostic controller with anticipated results wherein a mismatch indicates an actual malfunction in the suspect unit. Any detected malfunctions are reported to the data processing unit over the in-service data path.

Claims

1. In a system wherein a first and second remote logic unit respectively communicate with a local controlling logic unit over first and second data paths, a diagnostic controller in physical proximity to said remote logic units for diagnosing said first remote logic unit when said first data path is out-of-service and said second data path is in-service, comprising

means responsive to informtion received over said in-service data path from said controlling logic unit for generating test data and applying said test data to said remote first logic unit to simulate data received over said out-of-service data path,

means responsive to said first remote logic unit'"'"'s operations on said test data for detecting malfunctions in said first remote logic unit, and

means controlled by said detecting means for reporting any detected malfunctions over said in-service data path to said controlling logic unit.

2. The diagnostic controller in accordance with claim 1 wherein said information received from said controlling logic unit specifies an address, and wherein said generating and applying means comprises

an addressable memory storing said test data,

means responsive to said information received from said controlling logic unit for retrieving a test vector from said memory at an address related to said specified address, and

means for applying said retrieved test vector to said first remote logic unit to simulte data received over said out-of-service data path.

3. The diagnostic controller in accordance with claim 2 wherein said first remote logic unit operates in accordance with said retrieved test vector applied thereto and generates a response, and wherein said memory also stores an expected response, and wherein said detecting means comprises

means for controlling said retrieving means to retrieve said expected response from said memory,

means for comparing said retrieved expected response with said response from said first remote logic unit, and

means responsive to said comparing means for generating an error signal if a mismatch is detected between said compared responses.

4. The diagnostic controller in accordance with claim 3 wherein said memory also stores malfunction reports and wherein said reporting means comprises

means for controlling said retrieving means to retrieve a malfunction report from said memory, and

means for transmitting said retrieved malfunction report over said in-service data path to said controlling logic unit.

5. The diagnostic controller in accordance with claim 4 wherein said memory also stores progress reports and wherein said expected response controlling means controls said retrieving means to retrieve a progress report from said memory, and wherein said report transmitting means also transmits said retrieved progress report over said in-service data path to said controlling logic unit.

6. In a communication system wherein a pair of logic units are remotely situated in relation to a controlling data processing unit, and wherein each of said logic units communicates with said processing unit over a distinct data path associated therewith;

apparatus for diagnosing one of said logic units when the one data path associated therewith is not deemed fully operational, which comprises

means responsive to information from said processing unit received over the other of said data paths for generating test information and for applying said generated test information to said one logic unit to simulate information received over said one data path,

said one logic units being responsive to said applied test information for operating in accordance therewith and generating a response thereto,

means for providing an expected response,

means for comparing said generated response with said expected response,

means responsive to said comparing means for generating an error signal if a mismatch is detected, and

means responsive to said error signal for generating an error indication and for transmitting said error indication to said processing unit over said other data path.

7. The apparatus in accordance with claim 6 wherein said generating and applying means comprises

a memory storing test information,

means for addressing said memory at an address specified by said information from said processing unit to retrieve said test information therefrom,

register means for temporarily storing said retrieved test information,

gating means controllable to gate said retrieved test information from said register means to either of said logic units,

and means responsive to said information from said processing unit for controlling said gating means to gate said retrieved test information to said one logic unit.

8. The apparatus in accordance with claim 7 wherein said memory also stores said expected response, wherein said providing means comprises means for controlling said addressing means to retrieve said expected response from said memory, and wherein said comparing means comprises

first register means for temporarily storing a response from said one logic unit,

second register means for temporarily storing a response from the other of said logic units,

a comparator,

gating means controllable to gate said retrieved expected response to said comparator and controllable to gate the response stored in either of said first or second register means to said comparator, and

means responsive to said information from said processing unit for controlling said last-named gating means to gate said retrieved expected response and the response in said first register to said comparator.

9. The apparatus in accordance with claim 8 wherein said memory also stores said error indication, and wherein said generating and transmitting means comprises

means for controlling said addressing means to retrieve said error indication from said memory, and

means for applying said retrieved error indication to said other logic unit, said other logic unit being operative to transmit said applied retrieved error indication to said processing unit over said other data path.

10. In a communication system wherein a pair of communication units are remotely situated in relation to a controlling data processing unit and wherein each of said communication units communicates with said processing unit over a distinct data path uniquely associated therewith, apparatus for diagnosing one of said communication units when the one data path associated therewith is out-of-service, comprising

a memory for storing test vectors, expected responses, and reply words,

retrieving means responsive to information from said data processing unit received over the other of said data paths for retrieving a test vector and an expected response from said memory,

means for applying said retrieved test vector to said one communication unit to simulate data received over said one data path,

said one communication unit being operative in accordance with said applied test vector and generating a response thereto,

means for comparing said retrieved expected response with said generated response,

means responsive to said comparing means for generating an error signal if mismatch is detected,

means responsive to said error signal for controlling said retrieving means to retrieve a reply word from said memory, and

means for transmitting said retrieved reply word to said processing unit over said other data path.

11. The apparatus in accordance with claim 10 wherein said memory is a read-only memory, and wherein said retrieving means comprises

an address counter indicating the address of the next instruction to be retrieved from said memory,

means for setting said address counter to a starting address having a predetermined relation to an address indicated by said information from said data processing unit, and

means for incrementing the address in said address counter.

12. The apparatus in accordance with claim 11 wherein said controlling means comprises

register means responsive to said incrementing means for indicating the number of instructions retrieved from said memory, and

means responsive to said error signal for inhibiting the application of said address indicated by said address counter to said memory and for applying to said memory an address having a predetermined relation to the number indicated by said register means.

13. In a communication system wherein a pair of logic units are remotely situated in relation to a controlling data processing unit, and wherein each of said logic units communicates with said processing unit over a distinct data path associated therewith, and wherein one of said logic units and the one data path associated therewith are out-of-service, diagnostic apparatus comprising

a source of test vectors,

applying means responsive to information received from said data processing unit over the other data path for applying a plurality of said test vectors in a predetermined sequence to said one logic unit to simulate data received over said one data path,

said logic unit being operative in accordance with each of said test vectors applied thereto and generating a response for said each test vector,

a source of expected responses,

means for comparing each said generated response with an expected response and for generating an error signal if a mismatch is detected,

means responsive to said error signal for transmitting an error indication to said processing unit over said other data path,

timing means controlled by said error signal for timing a predetermined interval of time,

means responsive to said timing means for inhibiting said transmitting means for transmitting any more error indications to said processing unit for said predetermined time interval.

14. In a communication system wherein a pair of logic units are remotely situated in relation to a controlling data processing unit and wherein each of said logic units includes a signal distributor and communicates with said processing unit over a distinct data path associated therewith, apparatus for diagnosing one of said logic units and the ability of the signal distributor therein to generate commands when the data path associated with said one logic unit is out-of-service, comprising

a counter set to predetermined count and indicating the count thereof,

a memory storing an instruction,

means for retrieving said instruction,

first logic means responsive to said indicated count and to said retrieved instruction for generating a test vector,

means for applying said test vector to said one logic unit to simulate data received over said out-of-service data path,

said signal distributor in said one logic unit generating a command responsive to said applied test vector,

second logic means responsive to said indicated count and to said retrieved instruction for generating an expected command,

means for comparing said generated command with said expected command,

means responsive to said comparing means for generating an error signal if a mismatch occurs, and

means responsive to said error signal for transmitting an error indication to said processing unit over said other data path.

15. The diagnostic apparatus in accordance with claim 14 further comprising means responsive to the absence of said error signal for incrementing said counter and wherein said first logic means is responsive to said incremented count and said retrieved instruction for generating another test vector and said second logic means is responsive to said incremented count and said retrieved instruction for generating another expected command, whereby the successive incrementation of said count causes the generation of a plurality of test vectors and expected commands.

16. For use in a telephone system providing operator services wherein first and second duplicated control units are remotely situated in relation to a controlling data processing unit, and wherein a first data path is connected between said first control unit and said processing unit for the transmission of data therebetween, and a second data path is connected between said second control unit and said processing unit for the transmission of data therebetween, each of said control units comprising (1) a data set for receiving and transmitting data over the data path connected to said each control unit, (2) a scanner for scanning a plurality of trunks and operator positions and providing reports to said data set, and (3) a signal distributor responsive to data received by said data set for controlling said trunks and positions;

a diagnostic controller for diagnosing said first control unit when said first data path is out-of-service and said second data path is in-service, which comprises

a memory for storing a plurality of diagnostic instructions,

means responsive to information from said controlling data processing unit received over said second data path by the data set in said second control unit for retrieving a first diagnostic instruction from said memory,

means for decoding each instruction retrieved from said memory,

means responsive to said decoding means for applying at least a portion of said first instruction to said data set in said first control unit to simulate data received over said first data path,

said first control unit being operative in accordance with said first instruction, said signal distributor therein generating a command, and said scanner therein generating a report,

first means for controlling said retrieving means to retrieve a second instruction from said memory,

means responsive to said decoding means for comparing information specified by said second instruction with either said generated report or said generated command,

means connected to said comparing means for generating an error signal if a mismatch is detected,

second means responsive to said error signal for controlling said retrieving means to retrieve a third instruction from said memory, and

means responsive to said decoding means for applying at least a portion of said third instruction to said data set in said second control unit for conveyance to said controlling data processing unit over said second data path.

17. The diagnostic controller in accordance with claim 16 wherein said second controlling means controls said retrieving means to retrieve said third instruction from said memory at an address having a predetermined relationship to the number of instructions retrieved from said memory.

18. The diagnostic controller in accordance with claim 16 wherein said first diagnostic instruction is retrieved from said memory at an address indicated by said information from said controlling data processing unit.

19. The diagnostic controller in accordance with claim 16 wherein said comparing means comprises

a comparator,

first gating means for gating said information specified by said second instruction to said comparator,

second gating means selectively controllable to gate either said generated report or said generated command to said comparator, and

means responsive to said decoding means decoding said second instruction for controlling said second gating means.