| 摘要 |
PURPOSE:To diagnose the function of an error correcting circuit, by inverting the polarity of a redundant bit and treating intentionally the redundant bit as an erroneous redundant bit. CONSTITUTION:When a data is written to a storage part 1, a redundant bit 4 produced from a redundant bit producing circuit 3 is written on the basis of the data of writing register 2. When the data is read out of the part 1, the data and the bit 4 are stored in reading registers 5 and 6 respectively. The data output is fed to an error detecting circuit 7. The redundant bit output is fed to the circuit 7 via a polarity inverting circuit 8. The circuit 8 is controlled by a register 9 and in response to the bit. It is possible to invert the polarity of an optional bit of the redundant bit. The states of a 1-bit error, a 2-bit error, etc. can be freely generated by operating the register 9. This ensures the perfect diagnosis of the error detecting funtion. |
