| 摘要 |
PURPOSE:To reduce the frequency of error correcting operation by interchanging the address of a micro instruction word of high frequency in execution and that of low frequency in execution if trouble occurs in this address of the micro instruction word of high frequency in execution in a control memory. CONSTITUTION:When the occurrence of error is reported from an error detecting and correcting circuit 20 to an address conversion control circuit 50, the circuit 50 discriminates whether the address of the micro instruction word where error occurs is in a preliminarily determined address area of high frequency in execution or not in accordance with contents of a register 16. If this address is there, the control circuit 50 sends an address conversion indication to an address converting circuit 55 and instructs a control memory write control circuit 40 to load a microprogram to a control memory 10 again. The address converting circuit 55 converts address information from a selector 30 by the indication from the address conversion control circuit 50 so that two preliminarily determined address areas are interchanged, and converted information is supplied to the control memory 10. |
