| 摘要 |
PURPOSE:To prevent the occurrence of a correction unable state which is due to the overlap of 1-bit errors, by providing an access producing circuit to a storage part controller and giving an access also to the storage region that receives no access for a long period of time by a CPU, etc. CONSTITUTION:When a start is applied from a service processor SVP, a storage controller MCU is ready to check a data. Then an access port is controlled via a priority deciding circuit PRT, and no access is given to a buffer memory MCUBM by a CPU, etc. by the address given from an access producing circuit ACG of the controller MCU. Then an access is successively given to all addresses of a main storage device MSU which receives no access for a long period of time. The reading data of the device MSU is checked by a data checking circuit DCH, and a 1-bit error is corrected by an error correcting circuit CRT. Thus an access is given at a proper time point to all addresses of a storage device that receives no access from a CPU, etc. for a long time of period. In such a way, the occurrence of a correction unable state in which the 1-bit errors overlap each other due to the alpha rays, etc. can be prevented. |
