Testing data transmissions between fax modems through real time synchronization and resynchronization of asynchronous data

Claim 1

A method for testing data transmissions sent via a synchronous connection between first and second data transmission devices through the use of a computer having memory, the computer being coupled to the first and second data transmission devices via first and second asynchronous connections, respectively, the method comprising the steps of: (A) storing in memory a first sequence of data bits partitioned into units with each unit comprising N data bits; (B) storing in memory N-1 preshifted sequences of data bits with the data bits of each preshifted sequence being partitioned into units comprising N data bits, the first preshifted sequence formed by shifting the first sequence by one bit, and subsequent preshifted sequences formed by shifting the preceding preshifted sequence by one bit; (C) transmitting the data bits of the first sequence to the first device via the first asynchronous connection for re transmission to the second device via the synchronous connection; (D) receiving as input to the computer via the second asynchronous connection an input sequence of data bits transmitted from the second device, the input sequence partitioned into input units with each input unit comprising N data bits; (F) synchronizing the input sequence of data bits with one of the first and the N-1 preshifted sequences of data bits being designated as a synchronized sequence; (G) resynchronizing the input sequence of data bits with one of the first and N-1 preshifted sequences of data bits being designated as a resynchronized sequence when a bit disparity between corresponding units of the input sequence and the synchronized sequence occurs; (H) determining the cause of the bit disparity by calculating a bit shift number corresponding to a number of data bits the resynchronized sequence is shifted from the synchronized sequence; (I) continuing synchronization of the input sequence of data bits with the resynchronized sequence; (J) redesignating the resynchronized sequence as the synchronized sequence when a bit disparity between corresponding units of the input sequence and the resynchronized sequence occurs; and (K) performing steps (G) through (J) until all data bits of the first sequence have been transmitted and subsequently received by the computer.

Claim 2

A method for testing data transmissions sent via a synchronous connection between first and second data transmission devices through the use of a computer having memory, the computer being coupled to the first and second data transmission devices via first and second asynchronous connections, respectively, the method comprising the steps of: (A) storing in memory a first sequence of data bits partitioned into units with each unit comprising N data bits; (B) storing in memory N-1 preshifted sequences of data bits with the data bits of each preshifted sequence being partitioned into units comprising N data bits, the first preshifted sequence formed by shifting the first sequence by one bit, and subsequent preshifted sequences formed by shifting the preceding preshifted sequence by one bit; (C) transmitting the data bits of the first sequence to the first device via the first asynchronous connection for re transmission to the second device via the synchronous connection; (D) receiving as input to the computer via the second asynchronous connection an input sequence of data bits transmitted from the second device, the input sequence partitioned into input units with each input unit comprising N data bits; (F) synchronizing the input sequence of data bits with one of the first and the N-1 preshifted sequences of data bits being designated as a synchronized sequence; (G) resynchronizing the input sequence of data bits with one of the first and N-1 preshifted sequences of data bits being designated as a resynchronized sequence when a bit disparity between corresponding units of the input sequence and the synchronized sequence occurs; (H) determining the cause of the bit disparity by calculating a bit shift number corresponding to a number of data bits the resynchronized sequence is shifted from the synchronized sequence; (I) continuing synchronization of the input sequence of data bits with the resynchronized sequence; (J) redesignating the resynchronized sequence as the synchronized sequence when a bit disparity between corresponding units of the input sequence and the resynchronized sequence occurs; and (K) performing steps (G) through (J) until all data bits of the first sequence have been transmitted and subsequently received by the computer.

Claim 12

A method for testing data transmissions over a synchronous connection between first and second data transmission devices comprising fax modems through the use of a computer having memory, the computer being coupled to the first and second data transmission devices via first and second asynchronous connections, respectively, the method comprising the steps of: (A) storing in memory a first sequence of data bits partitioned into units with each unit comprising N data bits; (B) storing in memory N-1 preshifted sequences of data bits with the data bits of each preshifted sequence being partitioned into units comprising N data bits, each of the preshifted sequences comprising data bits corresponding to the data bits of the first sequence with a first preshifted sequence formed by shifting the first sequence as a whole by one data bit and each succeeding preshifted sequence formed by shifting each preceding preshifted sequence as a whole by one data bit in a direction from the least significant bit to the most significant bit in each case; (C) transmitting the data bits of the first sequence to the first device via the first asynchronous connection for retransmission to the second device via the synchronous connection; (D) receiving as input to the computer via the second asynchronous connection an input sequence of data bits transmitted from the second device; (F) partitioning the data bits of the input sequence into input units for comparison with the units of the first sequence and the preshifted sequences; (G) synchronizing consecutive input units of the input sequence with consecutive units in one of the first and N-1 preshifted sequences forming a matched sequence R; (H) resynchronizing a subsequent input unit of the input sequence with a corresponding subsequent unit of one of the first and the N-1 preshifted sequences forming a subsequently matched sequence M when a bit disparity occurs between data bits in corresponding units of the input sequence and the matched sequence R; (I) calculating a difference P between assigned numbers of the matched sequence R and the subsequently matched sequence M where P=R-M, the assigned numbers corresponding to a consecutive arrangement of the first and N-1 preshifted sequences with respect to the bit shifts between each of the first and N-1 sequences, with the assigned numbers increasing in magnitude as successive sequences contain more bit shifts; (J) recording as bit errors of the subsequent input unit of the input sequence non-matching data bit values between the subsequent input unit of the input sequence and the corresponding subsequent unit of the subsequently matched sequence when the difference P is zero; (K) recording as bit deletions in the subsequent input unit of the input sequence a number corresponding to an absolute value of the difference P when the difference P is a positive, non-zero value; (L) recording as bit insertions in the subsequent input unit of the input sequence a number corresponding to an absolute value of the difference P when the difference P is a negative, non-zero value; (M) continuing synchronization of consecutive units of the input sequence and the subsequently matched sequence; (N) redesignating the subsequently matched sequence as the matched sequence when a bit disparity occurs between corresponding units of the input sequence and the subsequently matched sequence; and (O) performing steps (H) through (N) until all data bits of the first sequence have been transmitted and subsequently received by the computer.

Claim 13

A method for testing data transmissions over a synchronous connection between first and second data transmission devices comprising fax modems through the use of a computer having memory, the computer being coupled to the first and second data transmission devices via first and second asynchronous connections, respectively, the method comprising the steps of: (A) storing in memory a first sequence of data bits partitioned into units with each unit comprising N data bits; (B) storing in memory N-1 preshifted sequences of data bits with the data bits of each preshifted sequence being partitioned into units comprising N data bits, each of the preshifted sequences comprising data bits corresponding to the data bits of the first sequence with a first preshifted sequence formed by shifting the first sequence as a whole by one data bit and each succeeding preshifted sequence formed by shifting each preceding preshifted sequence as a whole by one data bit in a direction from the least significant bit to the most significant bit in each case; (C) transmitting the data bits of the first sequence to the first device via the first asynchronous connection for retransmission to the second device via the synchronous connection; (D) receiving as input to the computer via the second asynchronous connection an input sequence of data bits transmitted from the second device; (F) partitioning the data bits of the input sequence into input units for comparison with the units of the first sequence and the preshifted sequences; (G) synchronizing consecutive input units of the input sequence with consecutive units in one of the first and N-1 preshifted sequences forming a matched sequence R; (H) resynchronizing a subsequent input unit of the input sequence with a corresponding subsequent unit of one of the first and the N-1 preshifted sequences forming a subsequently matched sequence M when a bit disparity occurs between data bits in corresponding units of the input sequence and the matched sequence R; (I) calculating a difference P between assigned numbers of the matched sequence R and the subsequently matched sequence M where P=R-M, the assigned numbers corresponding to a consecutive arrangement of the first and N-1 preshifted sequences with respect to the bit shifts between each of the first and N-1 sequences, with the assigned numbers increasing in magnitude as successive sequences contain more bit shifts; (J) recording as bit errors of the subsequent input unit of the input sequence non-matching data bit values between the subsequent input unit of the input sequence and the corresponding subsequent unit of the subsequently matched sequence when the difference P is zero; (K) recording as bit deletions in the subsequent input unit of the input sequence a number corresponding to an absolute value of the difference P when the difference P is a positive, non-zero value; (L) recording as bit insertions in the subsequent input unit of the input sequence a number corresponding to an absolute value of the difference P when the difference P is a negative, non-zero value; (M) continuing synchronization of consecutive units of the input sequence and the subsequently matched sequence; (N) redesignating the subsequently matched sequence as the matched sequence when a bit disparity occurs between corresponding units of the input sequence and the subsequently matched sequence; and (O) performing steps (H) through (N) until all data bits of the first sequence have been transmitted and subsequently received by the computer.