| 摘要 |
<p>In a high speed data processing system, there is provided a circuit for shifting either right or left as data is transmitted to or from the main storage unit. Apparatus for high speed parallel byte shifting is connected to the data bus which connects the main storage unit to the system and comprises logic which selects predetermined byte lines. Information from the individually selected byte lines is temporarily stored in parallel buffer registers and subsequently returned to a different byte line to provide byte shifting without the requirement of shift registers of complex logic. When predetermined byte lines to the byte shifters are selected, control means are provided to activate a set of shift select means connected to error checking circuits. The error checking circuits comprise logic gating means for checking the proper selection of byte lines and for storing a signal indicative of an error or absence of an input error in the error storage means. When the data byte is being transferred out or read out of the byte shifter, the error storage means is read out to determine the presence or absence of an output error from the error storage means.</p> |
