| 摘要 |
<p>PURPOSE:To improve the access speed to an external storage device, by providing a semiconductor storage device of an RAM and an ROM as the external storage device, and storing the operating system program of a microprocessor to the ROM. CONSTITUTION:The microprocessor (muPC) 1 is connected to a main storage device 2 with a line 11, and the external storage device 3 comprising the semiconductor storage device of the RAM31 and the ROM32 are connected by a data transfer line 12. The operating system OS is stored in the ROM32 and the OS is transferred to the device 2 via the line 12 at the start of the system. When the muPC1 accesses the contents of the device 3, the transfer start address of the device 3 is designated from the muPC1, and the data is transferred to the device 2 via the line 12 under the control of a DMA transfer control circuit 4, and the muPC1 performs accessing.</p> |
