| 摘要 |
PURPOSE:To enable many memory access using small number of address lines by dividing logical space using upper m-bit (n>m) out of n-bit of address lines into 2<m>, and using a space as a space for extension. CONSTITUTION:Specified values 5, 6 are set beforehand from the outside to a job register 2 and a mapping RAM3. As to input address of the RAM3, h-bit becomes upper address out of the job register 2 and k-bit becomes lower address out of logical memory address. In total, 2<h+k> kinds of mapping areas are selected. Consequently, 2<h+k> kinds of segments can be accessed. The number of segments is determined by number J of output of the RAM3 and maximum number is 2<j>. The memory address becomes 2<n-m-k+j>, and the physical address becomes greater than the logical address. However, it is supposed that J>m+K. |
