| 摘要 |
<p>PURPOSE:To read data in a device whose access time is long by providing a system clock prolonging means which extends the period of the clock of a microprocessor. CONSTITUTION:When a microprocessor 1 accesses a storage device 2, a device selecting device 4 detects this access to output a device select signal 11 to the storage device 2, and the storage device 2 receives this signal to start the operation, and the device selecting device 4 outputs a period extension indicating signal 9 to a clock period extending means 6. That is, the system clock period extending means 6 extends the period of a system clock 10 on demand. Thus, the data read timing of the microprocessor 1 is delayed to access the storage device 2 or a peripheral device 3 whose access time is long.</p> |
