| 摘要 |
PURPOSE:To convert RM data at high speeds by reading out the data to be converted from an RAM by controlling of a direct memory access DMA controller and writing the conversiondata from an ROM into the RAM. CONSTITUTION:When the holding signal 11 of a DMA controller CT2 is inputted to a CPU1, and the answer signal 12 from the CPU1 is inputted to the CT2, the initiative of system control shifts to the CT2. The data to be converted are read out from an RAM6 by controlling of the CT2, and these are held in an input register 5. An ROM4 storing the conversiondata is accessed by the address information of the register 5 and the conversiondata are read out from the ROM4 by the control signal of a control register 3 and are outputted to a data bus 8. The conversion data outputted to the bus 8 are written into the RAM6 by controlling of the CT2 and the data of the RAM6 are converted at high speeds without the intervention of the CPU. |
