| 摘要 |
PURPOSE: To automatically execute a complement/re-complement(C/R) error correction method when excess errors are detected in a main storage device MS. CONSTITUTION: The read request of the data unit DU of MS11 is given by a request source. When the excess errors are detected in an ECC logic circuit 13, the request is returned to the request source. The request source requests re-reading. Then, the C/R method is started with the request and reading is executed from MS11, Then, the excess errors are corrected. Then, DU+ECC is stored in a data buffer 21 and the circuit 13 generates a state bit and a parity bit to DU+ECC and they are stored in buffers 24 and 27. When the state bit shows the excess errors, an inverter 32 is activated, DU+ECC from the buffer 21 is inverted and it is stored in the corresponding position of MS 11. Then, DU+ECC which is inverted again in an inverter 12 is stored in the buffer 21 and it is stored in MS in second reading. |
