| 摘要 |
PURPOSE:To facilitate the self-diagnosis action whether or not the function of an EDC circuit is normal, without using an address line. CONSTITUTION:The writing data to a memory part 2 are inputted, the checking bit is prepared from the writing data, the checking bit is written into the memory part 2, and the data read out of a memory 2 and the checking bit are inputted. The device is constituted of an error detecting correcting means 3 to perform the error detection and correct the error if possible, a latch means 4 to hold the checking bit read from the memory part 2, and a multiplexer 5 to select the checking bit read out of the memory part 2 in a usual access action mode and select the checking bit held by the latch means 4 and give respectively to the error detecting correcting means 3 in a diagnosis action mode to diagnose the error detecting correcting means 3. |
