Control system for telephone switching system

Claim 2

In a telephony system including a plurality of telephones and interconnecting telephone lines for conveying signals from and to said telephones and call processing means connected to said telephone lines for selectively interconnecting the telephones and respective lines to establish communications between pairs of telephones, and wherein the call processing means includes a port means that connects to each telephone line and selective switching means for interconnecting selected pairs of the port means, the improvement of automatic test call means for testing the operation of the selective switching means, said automatic test call means comprising: A. selectable test access means in each port circuit means and connected to the corresponding telephone line for coupling signals from and to the telephone lines and for isolating the port means from the telephone lines, B. test call generating means for generating signals corresponding to telephone line signals during a calling operation, C. control means connected to said selectable test access means and said test call generating means for selecting a first test access means and a second test access means thereby to establish an input and output path for the signals from said test call generating means, whereby the call processing means processes the telephone test call between the selected port circuit means, and D. monitoring means connected to said control means and to the call processing means for monitoring the test call through the call processing means.

Claim 3

A telephony system as recited in claim 1 wherein each telephone is characterized by having an on-hook state and an off-hook state and each of these states is indicated by an electrical supervisory signal on the telephone line, said control means in said automatic test call means including line condition monitoring means for terminating a test call when either of the telephones on telephone lines connected to port means that are involved in a test call are in an off-hook condition.

Claim 4

A telephony system as recited in claim 2 wherein each of the port means includes means for generating supervisory signals and means for responding to sense signals that control the operation of the telephone and of the call processing means, and wherein said test call generating means includes means for simulating supervisory and control signals that are used during an automatic test call and said test call monitoring means includes means for monitoring the simulated supervisory and sense signals.

Claim 5

A telephony system as recited in claim 2 wherein said monitoring means includes reply register means including: i. first and second stages for indicating siezure of the port means connected to said first and second test access means, a third stage for indicating that a previously specified action initiated by said test call generating means has been completed, and a fourth stage indicating a failure to operate as commanded during the execution of a test call, ii. means for connecting said reply register means to said test call monitoring means, and iii. means connected to said reply register means for indicating the status of the call.

Claim 6

A telephony system as recited in claim 4 wherein said control means in said test call means includes means for performing a test call on a periodic basis, whereby each port means in said telephony system is periodically selected for connection to said first access means and periodically selected for connection to said second access means.

Claim 7

A telephony system as recited in claim 4 wherein said telephony system additionally includes maintenance means responsive to fault conditions in the call processing means for performing a plurality of tests including a call processing test, and wherein said control means in said automatic test call means includes means responsive to said maintenance means for initiating a test call between port means selected by said maintenance means.

Claim 8

A telephony system as recited in claim 4 wherein said control means in said automatic test call means includes: i. register means for storing command information that identifies the port means selected by said first test access means as a calling port means and that identifies predetermined characteristics of said port means, ii. called port parameter register means for storing information corresponding to predetermined characteristics of the port means connected to said second test access means, and iii. calling port action means for identifying the specific test call operation to be performed.

Claim 9

A telephony system as recited in claim 7 wherein said control means in said automatic test call means further includes register means for identifying whether the port means connected to said first or second test access means is to respond to an operation and expected response register means for identifying the response that should be detected by said test call monitoring means.

Claim 10

A telephony system as recited in claim 7 wherein said calling port action means includes means for storing a digit to be dialed during a dialing portion of a test call.

Claim 11

A telephony system as recited in claim 7 wherein said calling port action means includes means for initiating a tone for transfer through the call processing means.

Claim 12

A telephony system as recited in claim 7 wherein a test call comprises a sequence of test call operations and said control means in said automatic test call means includes variable timing means for establishing a timing sequence for the test call operations and the time for each test call operation.

Claim 13

In a telephony system including a plurality of telephones and interconnecting telephone lines for conveying signals from and to said telephones and call processing means connected to said telephone lines for selectively interconnecting the telephones and respective lines to establish communications between pairs of telephones, and wherein the call processing means includes a port means that connects to each telephone line and selective switching means for interconnecting selected pairs of the port means, the improvement of automatic test call means for testing the operation of the selective switching means, said automatic test call means comprising: A. Selectable test access means in each port means and connected to the corresponding telephone line for coupling signals from and to the telephone lines and for isolating the port circuit means from the telephone lines, B. test call generating means for generating signals corresponding to telephone line signals during a calling operation, C. control means connected to said selectable test access means and said test call generating means for selecting a first test access means and a second test access means thereby to establish an input and output path for the signals from said test call generating means, whereby the call processing means processes the telephone test call between the selected port circuit means, and D. test call monitoring means selectively connected to said second test access means for monitoring the signals at said second test access means during the test call.

Claim 14

In a telephony system including a plurality of telephones and interconnecting telephone lines for conveying signals from and to said telephones and call processing means connected to said telephone lines for selectively interconnecting the telephones and respective lines to establish communications between pairs of telephones, and wherein the call processing means includes a port means that connects to each telephone line and selective switching means for interconnecting selected pairs of the port means, the improvement of automatic test call means for testing the operation of the selective switching means, said automatic test call means comprising: A. Selectable test access means in each port means and connected to the corresponding telephone line for coupling signals from and to the telephone lines and for isolating the port circuit means from the telephone lines, B. test call generating means for generating signals corresponding to telephone line signals during a calling operation, C. control means connected to said selectable test access means and said test call generating means for selecting a first test access means and a second test access means thereby to establish an input and output path for the signals from said test call generating means, whereby the call processing means processes the telephone test call between the selected port circuit means, and D. test call monitoring means selectively connected to said second test access means for monitoring the signals at said second test access means during the test call.

Claim 15

A telephony system as recited in claim 12 wherein each telephone is characterized by having an on-hook state and an off-hook state and each of these states is indicated by an electrical supervisory signal on the telephone line, said control means in said automatic test call means including line condition monitoring means for terminating a test call when either of the telephones on telephone lines connected to port means that are involved in a test call are in an off-hook condition.

Claim 16

A telephony system as recited in claim 13 wherein said control means in said test call means includes means for performing a test call on a periodic basis, whereby each port means in said telephony system is periodically selected for connection to said first access means and periodically selected for connection to said second access means.

Claim 17

A telephony system as recited in claim 13 wherein said telephony system additionally includes maintenance means responsive to fault conditions in the call processing means for performing a plurality of tests including a call processing test, and wherein said control means in said automatic test call means includes means responsive to said maintenance means for initiating a test call between port means selected by said maintenance means.

Claim 18

A telephony system for routing communications over a plurality of telephone lines, said system comprising: A. port means connected to the telephone lines for receiving signals therefrom and for transmitting signals thereto, B. first and second parallel, independently and synchronously operable call processing means for interconnecting, on a selective basis, certain of the telephone lines, each said call processing means operating concurrently in response to the same signals from the port means by generating output signals, C. controllable switching means interposed between said port means and both said call processing means for coupling the output signals from a selected one of said call processing means to said port means to complete communications between said port means and the selected one of said call processing means, D. selectable test access means in each said port means connected to the corresponding telephone and telephone line for coupling signals from and to said telephone lines and for isolating said port means from the telephone lines, E. test call means connected to said selectable test access means for effecting test calls through the selectable test access means, said test call means comprising: i. test call generating means for generating signals corresponding to telephone line signals during a calling operation, ii. control means connected to said selectable test access means and said test call generating means for selecting a first test access means and a second test access means for establishing an input and an output path for the signals from said test call generating means, whereby said call processing means processes the telephone test call between the selected port means, and iii. test call monitoring means selectively connected to said second test access means by said control means for monitoring the signals at said second test access means during the test call, F. fault monitoring means connected to each said call processing means for generating fault signals in response to fault conditions in said call processing means, including fault signals generated in response to a test call, and G. switchover means connected to said fault monitoring means, said controllable switching means, said test call monitoring means, and both said call processing means and operable independently of both said call processing means thereby to test each said call processing means in response to certain of said fault signals and identify one of said call processing means as the source of the fault condition and to cause said controllable switching means to couple output signals from the other of said call processing means to said port means.

Claim 19

A telephony system for routing communications over a plurality of telephone lines, said system comprising: A. port means connected to the telephone lines for receiving signals therefrom and for transmitting signals thereto, B. first and second parallel, independently and synchronously operable call processing means for interconnecting, on a selective basis, certain of the telephone lines, each said call processing means operating concurrently in response to the same signals from the port means by generating output signals, C. controllable switching means interposed between said port means and both said call processing means for coupling the output signals from a selected one of said call processing means to said port means to complete communications between said port means and the selected one of said call processing means, D. selectable test access means in each said port means connected to the corresponding telephone and telephone line for coupling signals from and to said telephone lines and for isolating said port means from the telephone lines, E. test call means connected to said selectable test access means for effecting test calls through the selectable test access means, said test call means comprising: i. test call generating means for generating signals corresponding to telephone line signals during a calling operation, ii. control means connected to said selectable test access means and said test call generating means for selecting a first test access means and a second test access means for establishing an input and an output path for the signals from said test call generating means, whereby said call processing means processes the telephone test call between the selected port means, and iii. test call monitoring means selectively connected to said second test access means by said control means for monitoring the signals at said second test access means during the test call, F. fault monitoring means connected to each said call processing means for generating fault signals in response to fault conditions in said call processing means, including fault signals generated in response to a test call, and G. switchover means connected to said fault monitoring means, said controllable switching means, said test call monitoring means, and both said call processing means and operable independently of both said call processing means thereby to test each said call processing means in response to certain of said fault signals and identify one of said call processing means as the source of the fault condition and to cause said controllable switching means to couple output signals from the other of said call processing means to said port means.

Claim 20

A telephony system as recited in claim 16 wherein each telephone is characterized by having an on-hook state and an off-hook state and each of these states is indicated by an electrical supervisory signal on the telephone line, said control means in said automatic test call means including line condition monitoring means for terminating a test call when either of the telephones on telephone lines connected to port means that are involved in a test call are in an off-hook condition.

Claim 21

A telephony system as recited in claim 17 wherein said test call monitoring means includes reply register means including: (a) first and second stages for indicating siezure of said port means connected to said first and second test access means, a third stage for indicating that a previously specified action initiated by said test call generating means has been completed, and a fourth stage indicating a failure to operate as commanded during the execution of a test call, (b) means for connecting said reply register means to said test call monitoring means, and (c) means connected to said reply register means for indicating the status of the call.

Claim 22

A telephony system as recited in claim 18 wherein said control means in said test call means includes means for performing a test call on a periodic basis, whereby each said port means in said telephony system is periodically selected for connection to said first access means and periodically selected for connection to said second access means.

Claim 23

A telephony system as recited in claim 18 wherein said telephony system additionally includes maintenance means responsive to fault conditions in the call processing means for performing a plurality of tests including a call processing test, and wherein said control means in said automatic test call means includes means responsive to said maintenance means for initiating a test call between said port means selected by said maintenance means.

Claim 24

A telephony system as recited in claim 16 wherein said test call access means includes relay means for interconnecting said automatic test call means to selectable ones of said port means and wherein said test call monitoring means includes means for monitoring the operation of said relay means.