APPARATUS AND METHOD FOR CONVERTING DIGITAL WORDS OR BYTES OF A GIVEN NUMBER OF BITS TO BYTES OF A DIFFERENT NUMBER OF BITS

摘要

Apparatus (60; 220; 600; 800; 1000) and method (70; 300; 500; 700; 900) are provided for converting, at high speed, without queuing of data, and with absolute accuracy, parallel bytes of digital data having a given number of binary bits as employed by one class of equipment to parallel bytes having a different (greater or smaller) number of bits as employed by another class of equipment. Such conversion is necessary in order to make possible unimpeded communication between the two classes of equipment. Converting of bytes is accomplished by momentarily storing as current data and as remainder data respective bits of successive incoming bytes clock count by clock count (70; 300; 500; 700; 900); identifying within each count a desired number of bits stored as remainder data, or current data, or both and grouping them into a set of bits to be outputted as an outgoing byte during a respective count; outputting such sets of bits clock count by clock count as outgoing bytes such that the outgoing bytes each have a different number of bits versus the number of bits in each incoming byte, and the outgoing bits have a desired numerical sequence; and periodically compensating (1/2 count; NOP, EOP) for the total number of bits outputted versus the number inputted during a given period of time.