| 摘要 |
PROBLEM TO BE SOLVED: To confirm quickly and surely normality of a flash memory without a load on a CPU and to enable outputting a result. SOLUTION: This device is provided with a memory 2 for checking contents other than a memory 1 used for normal processing, a counter circuit 4 as an address generating means for test, an XOR circuit 7 as a discriminating means and a D type flip-flop 10, buffer circuits 5 and 6 as a control means, a switching control circuit 8, a switch circuit 9, and an inverter 11. In a normal mode, the buffer circuits 5 and 6 are controlled so that an address generated in the CPU 1 is made valid, and in a test mode, the buffer circuits 5 and 6 are controlled so that an address generated in the counter circuit 4 is made valid. Data held in the same address of the memories 2 and 3 is read out, it is discriminated whether both are coincident or not and a check discrimination output is automatically generated.
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