| 摘要 |
<P>PROBLEM TO BE SOLVED: To surely perform power-on reset processing of a memory card to sharply enhance reliability even when power supply voltage supplied from a host is unstable. <P>SOLUTION: In initial setting of the memory card 1, flash confirmation data FD stored in a flash memory 2 is read, the data FD is compared with data FD1<SB>1</SB>for operation confirmation preliminarily stored in a ROM, if there is not abnormality, writing confirmation data FD1<SB>2</SB>stored in a ROM 4a is written in the flash memory 2, the data is read again and compared with the writing confirmation data FD1<SB>2</SB>in the ROM 4a. If there is not abnormality in data comparison between them, a CPU 4c determines that the flash memory is normal. In addition, in the case the data comparison is abnormal, the CPU 4c sets reset processing abnormality data in a register 5a to put its controller 3 into a sleep mode. When a command CMD is received during this period, the data comparison is executed again. <P>COPYRIGHT: (C)2008,JPO&INPIT |
