초록 ▼

An apparatus for reordering frames of data within an interface device of a receiving device. The present invention can switch context to allow frames associated with more than one sequence to be handled concurrently. A “Missing Frame Window”is generated and associated with each sequence. Each Missin

An apparatus for reordering frames of data within an interface device of a receiving device. The present invention can switch context to allow frames associated with more than one sequence to be handled concurrently. A “Missing Frame Window”is generated and associated with each sequence. Each Missing Frame Window maintains a record of frames of a particular sequence received out of order. When a frame associated with a particular sequence is received out of order, a bit within the Missing Frame Window representing the “missing”frame is asserted to represent receipt of the out of order frame. The out of order frame is then stored to be transferred to a host in order upon receipt of those frames which must be transferred before transfer of the out of order frame.

대표청구항 ▼

An interface device for coupling a receiving device to a communications link and for ensuring that frames of data received by the interface device, each frame being included within a sequence of frames, are communicated to the receiving device in a predetermined order defined by an external transmit

An interface device for coupling a receiving device to a communications link and for ensuring that frames of data received by the interface device, each frame being included within a sequence of frames, are communicated to the receiving device in a predetermined order defined by an external transmitting device, the interface device including: (a) a control circuit for processing information contained in each frame of data; and (b) a comparator window circuit coupled to, and controlled by, the control circuit, wherein each valid frame received by the interface device is associated with a value that indicates the relative position of that frame within the predetermined order, the comparator window circuit having: (1) a missing frame window storing means for storing a missing frame window which indicates whether the last received frame is the next expected frame in the order defined by the external transmitting device, (2) a counter, operatively coupled to the control circuit, for storing the value associated with the next expected frame and capable of incrementing the value stored in the counter by a predetermined value upon command from the control circuit when the missing frame window indicates that the last received frame is the next expected frame, (3) a comparator, coupled to the counter and the control circuit, for comparing a value associated with the next expected frame with a value associated with a last received frame and indicating whether the value associated with the last received frame is within a predetermined range of values relative to the value of the next expected frame, and (4) a shift register coupled to the control circuit and coupled to an input to the missing frame window storing means, such that a missing frame window input to the missing frame window storing means may be shifted under the control of the control circuit prior to being stored in the missing frame window storing means when the missing frame window indicates that the last received frame is the next expected frame.