| 摘要 |
PURPOSE:To surely detect faults in plural memory cards by providing an internal abnormality informing signal suppression means, and suppressing the output of an internal abnormality informing signal when a unit control register is set so as to set all the memory units at inoperable states. CONSTITUTION:When the fault is detected by an internal fault detection circuit 21, the internal abnormality informing signal is outputted by the unit control register CR. The fault in the memory card is detected at the outside by the internal abnormality informing signal, and when setting on the unit control register CR from the outside is performed so as to set all the memory units at the inoperable states, the output of the internal abnormality information signal to the outside is suppressed by the internal abnormality informing signal suppression means 24. Thereby, it is possible to prevent the overlap of the internal abnormality informing signals from plural memory cards occurring, and to prevent the detection of the fault at the outside from missing. |
