| 摘要 |
PURPOSE:To realize the diagnosis of a redundant bit producing circuit with use of the software, etc., by transferring the redundant bit of a read data given from an external storage device to a transfer device with a diagnosis read command provided to an external storage controller and then examining the contents of the redundant bit. CONSTITUTION:When a diagnosis read command is executed, an AND gate AND3 is opened at both a data part DATA and a part CRC. Thus the read data RD is transferred to a transfer device via a series-parallel converting circuit 2 in the form of the transfer information TTD. Accordingly the correct and incorrect CRC data are written with a diagnosis write command and then read with a read command. In the case of the correct CRC data, no error is reported; and an error is reported with an incorrect CRC data respectively. This fact is confirmed to perform the diagnosis for a CRC code inspecting circuit 4. |
