| 摘要 |
PURPOSE:To enable parity check to an address without increasing the number of parity bits at storage section, by selecting one of parity generation and check circuit for data or address and making it effective. CONSTITUTION:When a contact D of a parity check control section 80 is selected and an output of the control section 80 is at low level, a parity generating circuit 32 for data is selected via a write-in signal selecting circuit 70, and a data parity error signal gate circuit 82 is open and a read data parity check circuit 60 is selected. When this contact D is switched to a contact A, an address parity generating circuit 22 and an address parity check circuit 64 are selected similarly, and the parity check for address is made. Through the selection of one of a data system or an address system, the parity bit of a storage section 10 is not increased and thus, the parity check can be made to the address without making complicated the constitution. |
