| 摘要 |
<p>PURPOSE:To perform the read/write check of a RAM at a high speed by applying a DMA system to perform said read/write check of the RAM when this RAM is started. CONSTITUTION:A direct memory access DMA control part 3, a data register 4 and a comparator 5 are provided in addition to a processor 1 and a RAM 2. The processor 1 writes data in the register 4 and the part 3 is started to write the data of the register 4 in the entire part of the RAM 2. Then the part 3 reads the data out of the register 4 and the comparator 5 compares successively data stored in the register 4 with each other. All data written in the RAM 2 are successively compared with each other by the comparator 5. If discordance is detected, the comparator 5 reports this discordance to the processor 1 for check of the state of the RAM 2. In this case, the RAM 2 can be quickly checked since the part 3 performs its working at a high speed unlike the soft processing speed of the processor 1.</p> |
