Method of testing bit errors in isdn circuits

Claim 1

A method of testing for errors in an ISDN circuit having a bus including T-lines and R-lines for connecting a plurality of terminals to a network which includes a digital service unit, comprising the steps of: providing a test unit which includes a sending circuit having a B channel for sending out data on the T-lines, a receiving circuit having a B channel for receiving data from the R-lines, a protocol controller which executes channel D call control procedures, a pattern generator which generates a known data pattern, a selector which receives the data pattern of the pattern generator and sends a predetermined logic level or the data pattern of the pattern generator selectively to the sending circuit according to a control signal provided by the protocol controller, and an error detector which receives output data from the receiving circuit and detects errors by comparing the output data of the receiving circuit and the data pattern of the pattern generator; connecting said test unit to said bus; using the protocol controller to establish a test B channel which permits B channel communication between said sending circuit and said receiving circuit and which utilizes said T-lines and said network and said R-lines and said B channels of said sending circuit and said receiving circuit so that data sent out on the B channel of the sending circuit is received through the B channel of the receiving circuit; switching the selector by means of the control signal from said protocol controller so that the data pattern generated by the pattern generator is applied to the sending circuit as input test data for the test B channel; sending the input test data through the test B channel via the T-lines using the sending circuit, and receiving output test data from the test B channel via the R-lines using the receiving circuit; and using the error detector to compare the output test data to the input test data.

Claim 2

A method of testing for errors in an ISDN circuit having a bus including T-lines and R-lines for connecting a plurality of terminals to a network which includes a digital service unit, comprising the steps of: providing a test unit which includes a sending circuit having a B channel for sending out data on the T-lines, a receiving circuit having a B channel for receiving data from the R-lines, a protocol controller which executes channel D call control procedures, a pattern generator which generates a known data pattern, a selector which receives the data pattern of the pattern generator and sends a predetermined logic level or the data pattern of the pattern generator selectively to the sending circuit according to a control signal provided by the protocol controller, and an error detector which receives output data from the receiving circuit and detects errors by comparing the output data of the receiving circuit and the data pattern of the pattern generator; connecting said test unit to said bus; using the protocol controller to establish a test B channel which permits B channel communication between said sending circuit and said receiving circuit and which utilizes said T-lines and said network and said R-lines and said B channels of said sending circuit and said receiving circuit so that data sent out on the B channel of the sending circuit is received through the B channel of the receiving circuit; switching the selector by means of the control signal from said protocol controller so that the data pattern generated by the pattern generator is applied to the sending circuit as input test data for the test B channel; sending the input test data through the test B channel via the T-lines using the sending circuit, and receiving output test data from the test B channel via the R-lines using the receiving circuit; and using the error detector to compare the output test data to the input test data.

Claim 4

A method of testing for errors in an ISDN circuit having a bus including T-lines and R-lines for connecting a plurality of terminals of a network which includes a digital service unit, comprising the steps of: providing a test unit which includes a sending circuit having a plurality of B channels for sending out data on the T-lines, a receiving circuit having a plurality of B channels for receiving data from the R-lines, a protocol controller which executes channel D call control procedures, pattern generators which generate known data patterns, selectors which receive the data patterns from the pattern generators and send a predetermined logic level or the data patterns of the pattern generators selectively to the sending circuit according to control signals provided by the protocol controller, and error detectors which receive output data from the receiving circuit and detect errors by comparing the output data of the receiving circuit and the data patterns of the pattern generators; connecting said test unit to said bus; using the protocol controller to establish a plurality of test B channels which permit B channel communication between said sending circuit and said receiving circuit and which utilize said T-lines and said network and said R-lines and selected B channels of both said sending circuit and said receiving circuit so that data sent out on a first selected B channel of the sending circuit is received through a first selected B channel of the receiving circuit, and so that data sent out on a second selected B channel of the sending circuit is received through a second selected B channel of the receiving circuit; switching the selectors by means of the control signals from said protocol controller so that the data patterns generated by the pattern generators are applied to the sending circuit as input test data for the test B channels; sending the input test data through the test B channels via the T-lines using the sending circuit, and receiving output test data from the test B channels via the R-lines using the receiving circuit; and using the error detectors to compare the output test data to the input test data.

Claim 5

A method of testing for errors in an ISDN circuit having a bus including T-lines and R-lines for connecting a plurality of terminals of a network which includes a digital service unit, comprising the steps of: providing a test unit which includes a sending circuit having a plurality of B channels for sending out data on the T-lines, a receiving circuit having a plurality of B channels for receiving data from the R-lines, a protocol controller which executes channel D call control procedures, pattern generators which generate known data patterns, selectors which receive the data patterns from the pattern generators and send a predetermined logic level or the data patterns of the pattern generators selectively to the sending circuit according to control signals provided by the protocol controller, and error detectors which receive output data from the receiving circuit and detect errors by comparing the output data of the receiving circuit and the data patterns of the pattern generators; connecting said test unit to said bus; using the protocol controller to establish a plurality of test B channels which permit B channel communication between said sending circuit and said receiving circuit and which utilize said T-lines and said network and said R-lines and selected B channels of both said sending circuit and said receiving circuit so that data sent out on a first selected B channel of the sending circuit is received through a first selected B channel of the receiving circuit, and so that data sent out on a second selected B channel of the sending circuit is received through a second selected B channel of the receiving circuit; switching the selectors by means of the control signals from said protocol controller so that the data patterns generated by the pattern generators are applied to the sending circuit as input test data for the test B channels; sending the input test data through the test B channels via the T-lines using the sending circuit, and receiving output test data from the test B channels via the R-lines using the receiving circuit; and using the error detectors to compare the output test data to the input test data.

Claim 7

A method for testing for errors in an ISDN circuit having a bus including T-lines and R-lines for connecting a plurality of terminals to a switching network, comprising the steps of: providing a test unit which includes a sending circuit having at least one B channel for transmitting data on the T-lines, a receiving circuit having at least one B channel for receiving data from the R-lines, and a protocol controller for executing D channel call control procedures; connecting said test unit to said data bus with said sending circuit connected to said T-lines and said receiving circuit connected to said R-lines; using the protocol controller to establish at least one test B channel which permits B channel communication between said sending circuit and said receiving circuit and which utilizes said T-lines and said switching network and said R-lines and selected B channels of both said sending circuit and said receiving circuit so that data transmitted on a selected B channel of the sending circuit is received on a selected B channel of the receiving circuit; using the sending circuit to send into test data through the test B channel; using the receiving circuit to receive output test data from the test B channel; and comparing the output test data to the input test data.

Claim 8

A method for testing for errors in an ISDN circuit having a bus including T-lines and R-lines for connecting a plurality of terminals to a switching network, comprising the steps of: providing a test unit which includes a sending circuit having at least one B channel for transmitting data on the T-lines, a receiving circuit having at least one B channel for receiving data from the R-lines, and a protocol controller for executing D channel call control procedures; connecting said test unit to said data bus with said sending circuit connected to said T-lines and said receiving circuit connected to said R-lines; using the protocol controller to establish at least one test B channel which permits B channel communication between said sending circuit and said receiving circuit and which utilizes said T-lines and said switching network and said R-lines and selected B channels of both said sending circuit and said receiving circuit so that data transmitted on a selected B channel of the sending circuit is received on a selected B channel of the receiving circuit; using the sending circuit to send into test data through the test B channel; using the receiving circuit to receive output test data from the test B channel; and comparing the output test data to the input test data.