Method and apparatus for alignment of frames of information

Claim 1

A method of aligning frames of information transmitted between at least two devices, wherein devices transmit pending frames of information and receive frames of information, comprising the steps of: 1) initializing each device to a misaligned state; 2) each device when in the misaligned state repetitively transmitting a `start of alignment sequence`; 3) each device when in the misaligned state, transitioning to a realignment state upon receipt of a `start of alignment sequence`; 4) each device when in the realignment state transmitting an `end of alignment sequence`; 5) each device when in the realignment state remaining in said state until an `end of alignment sequence` is received, at which time each said device transitions to an aligned state; 6) each device when in the aligned state transmitting any pending frames of information; and 7) each device when in the aligned state remaining in said state until a frame alignment error, with respect to any received frame of information, is detected, at which time said device transitions to the misaligned state, and further wherein at least the `start of alignment sequence` is a frame alignment error.

Claim 2

A method of aligning frames of information transmitted between at least two devices, wherein devices transmit pending frames of information and receive frames of information, comprising the steps of: 1) initializing each device to a misaligned state; 2) each device when in the misaligned state repetitively transmitting a `start of alignment sequence`; 3) each device when in the misaligned state, transitioning to a realignment state upon receipt of a `start of alignment sequence`; 4) each device when in the realignment state transmitting an `end of alignment sequence`; 5) each device when in the realignment state remaining in said state until an `end of alignment sequence` is received, at which time each said device transitions to an aligned state; 6) each device when in the aligned state transmitting any pending frames of information; and 7) each device when in the aligned state remaining in said state until a frame alignment error, with respect to any received frame of information, is detected, at which time said device transitions to the misaligned state, and further wherein at least the `start of alignment sequence` is a frame alignment error.

Claim 6

A method of aligning frames of information as defined in claim. 2, wherein the `end of alignment sequence` comprises N multiples of P bits all in the first logic state, and ends with P minus 1 bits all in the first logic state and the Pth bit in the second logic state, where N is an integer greater than zero.

Claim 16

A system for aligning frames of information transmitted between at least two devices, wherein devices transmit pending frames of information and receive frames of information, and wherein each frame of information comprises units of information, comprising: A) means for initializing each device to a misaligned state; B) each device when in the misaligned state, having means for repetitively transmitting a `start of alignment sequence`; C) each device when in the misaligned state, having means for transitioning to a realignment state upon receipt of a `start of alignment sequence`; D) each device when in the realignment state transmitting an `end of alignment sequence`; E) each device when in the realignment state having means for remaining in said state until an `end of alignment sequence` is received, at which time each said device has means for transitioning to an aligned state; F) each device when in an aligned state transmitting any pending frames of information; and G) each device when in the aligned state having means for remaining in said state until a frame alignment error is detected, at which time said device has means for transitioning to the misaligned state, and further wherein at least a `start of alignment sequence` is a frame alignment error.

Claim 17

A system for aligning frames of information transmitted between at least two devices, wherein devices transmit pending frames of information and receive frames of information, and wherein each frame of information comprises units of information, comprising: A) means for initializing each device to a misaligned state; B) each device when in the misaligned state, having means for repetitively transmitting a `start of alignment sequence`; C) each device when in the misaligned state, having means for transitioning to a realignment state upon receipt of a `start of alignment sequence`; D) each device when in the realignment state transmitting an `end of alignment sequence`; E) each device when in the realignment state having means for remaining in said state until an `end of alignment sequence` is received, at which time each said device has means for transitioning to an aligned state; F) each device when in an aligned state transmitting any pending frames of information; and G) each device when in the aligned state having means for remaining in said state until a frame alignment error is detected, at which time said device has means for transitioning to the misaligned state, and further wherein at least a `start of alignment sequence` is a frame alignment error.

Claim 30

A system for aligning frames of information transmitted between at least two devices, wherein each frame of information comprises a first plurality of bits, with at least one bit in a second logic state designates the end of each frame, said system having means for interconnecting said devices to each other; said system further comprising for each device; A) means for receiving and storing information (receive shift register 64) from the interconnecting means; B) means (receive storage register 68) interconnected to the receiving and storing means, for assembling said received and stored information into frames; C) means (60, 72, 76), interconnected to the receiving and storing means (64) and the receive storage register (68), for determining if a frame alignment error exists with respect to each received frame of information; D) means (62, 92, 98), interconnected to the error determining means, for sequentially transmitting a first series of information bits all in a first logic state if a frame alignment error is detected; E) means (62, 92, 98) for transmitting at least one bit of information in a second logic state if said device receives a first series of information bits all in a first logic state after said device has detected a frame alignment error; and F) means (60) for entering an aligned state if said device has received at least one bit of information in the second logic state after receiving a series of information bits all in the first logic state after said device has detected a frame alignment error, and for causing the transmission of frames of information if said device is in the aligned state, wherein a frame alignment error includes detection of a first series of information bits all in a first logic state when said device is in the aligned state.

Claim 31

A system for aligning frames of information transmitted between at least two devices, wherein each frame of information comprises a first plurality of bits, with at least one bit in a second logic state designates the end of each frame, said system having means for interconnecting said devices to each other; said system further comprising for each device; A) means for receiving and storing information (receive shift register 64) from the interconnecting means; B) means (receive storage register 68) interconnected to the receiving and storing means, for assembling said received and stored information into frames; C) means (60, 72, 76), interconnected to the receiving and storing means (64) and the receive storage register (68), for determining if a frame alignment error exists with respect to each received frame of information; D) means (62, 92, 98), interconnected to the error determining means, for sequentially transmitting a first series of information bits all in a first logic state if a frame alignment error is detected; E) means (62, 92, 98) for transmitting at least one bit of information in a second logic state if said device receives a first series of information bits all in a first logic state after said device has detected a frame alignment error; and F) means (60) for entering an aligned state if said device has received at least one bit of information in the second logic state after receiving a series of information bits all in the first logic state after said device has detected a frame alignment error, and for causing the transmission of frames of information if said device is in the aligned state, wherein a frame alignment error includes detection of a first series of information bits all in a first logic state when said device is in the aligned state.