| 摘要 |
PURPOSE:To prevent the erroneous access to bank areas, by selcting a specific bank area independently of contents of the bank register in case of performing DMA. CONSTITUTION:When the control part performs DMA to the main storage part, the DMA signal becomes ''H'', and the address designation for decoder output addresses E000-FFFF input through address bus 7 is supplied to bank area MEM1 through AND gate AG3 and OR gate OG1. That is, bank area MEM1 is accessed certainly without the influence of contents of bank register 1 for switching of bank areas. |
