| 摘要 |
PURPOSE:To prevent the destruction of storage contents in a memory by providing a beak-up buffer to a memory means to store the identification data and judging the change of the identification data. CONSTITUTION:The specific data is stored in a RAM 1 by a data writing means 2 before the start of the working. When the TRAP processing is carried out, the specific date is taken out of the RAM 1 by a data reading means 3. A decision control means 4 compares both date with each other and controls the contents of the RAM 1 with an initialization means 5 based on the result of comparison. If no coincidence is obtained between both data, the RAM 1 is cleared. Meanwhile the RAM 1 is not cleared and initialized if the coincidence is obtained between both data. That is, 2- to 3-byte back-up buffer is provided to the RAM 1 to store the specific data. Then the specific data on the back-up buffer is checked when a CPU carries out the TRAP processing. If the specific data has no change, the RAM 1 is not cleared and its storage contents are held. |
