| 摘要 |
<p>PURPOSE:To reduce the unncessary power consumption of an output driver and a noise, at an address changing point by making an outside address bus output to a low level or high level fixed output corresponding to an inside resource address. CONSTITUTION:In an inside resource read period, an inside/outside display signal EXT is 'L', so that a data selection signal MLTD and an address selection signal MLTA becomes 'C' (non-selection), and only a fixed selection signal MLTL becomes 'H' (selection). Thus, in a multiplexer circuit 24, only a transmission gate 27 is opened, a fixed value 'L' is selected and outputted, and a data address output control signal IOC is outputted to an outside address/data bus in an 'H' period. And also, because the inside/outside display signal EXT is 'L' a read/write signal and a data enable signal become 'H' fixed outputs, and both a write signal and a read signal becomes 'H' signals.</p> |
