| 摘要 |
<p>PURPOSE:To obtain a device where the function corresponding to double buffering is implemented with hardware, by providing a microprocessor private area and a data exchange area and exchanging the data exchange area by a selecting circuit. CONSTITUTION:A microprocessor private area and a data exchange area are provided, and the data exchange area is exchanged by a selecting circuit. For example, outputs from the first and the second counters 31 and 34 are inputted to the first and the second main memory blocks 33 and 36 respectively independently of the presence or the absence of a selecting signal on an instruction line 316, and outputs from the first and the second counters 31 and 34 are inputted to the first and the second memory blocks for exchange through a selecting means 37 in accordance with the presence or the absence of the selecting signal on the instruction line 316. When the selecting signal is absent, the first and the second main memory blocks 33 and 36 and the first and the second memory blocks 32 and 35 for exchange are arranged in the same address space; and when the selecting signal is present, the access to the first and the second memory blocks 32 and 35 for exchange is reversed.</p> |
