| 摘要 |
<p>PURPOSE:To improve the executing speed by providing a stack area in a built-in RAM to which a high speed access is possible and executing an access to an external memory only when the internal stack is filled. CONSTITUTION:A microcomputer 100 contains a circuit part 30 which is provided with a stack area in a RAM 2 containing an internal stack and decides a stack state. When the data are successively saved into the internal stack and then this stack is filled with data and enable to save data any more, the data equivalent to two bytes are written into an external memory (external stack) 6 to reuse the idle internal stack equivalent to two bytes. On the contrary, when the saved data are returned from the internal stack, the data are returned from the internal stack at an internal stack area written into the stack 6. Then the data equivalent to two bytes are read again to the internal stack from the stack 6. Thus the executing speed of a microcomputer is increased with reuse of the internal stack.</p> |
