| 摘要 |
PURPOSE:To maximize the processing ability of a high-speed microcomputer, and to provide a device suitable for controlling automobile in an integrated manner, relationally at a low cost by storing one or more interruption processing program in a ROM contained in a one-chip microcomputer. CONSTITUTION:The value of a free-run counter 101 is taken in by an input capture register 100 built in a microcomputer 129, as a signal output from a car-speed sensor 9 rises, and interruption request is generated in a CPU 112, by which a car-speed detection program is processed by using a built-in RAM 111 and a built-in ROM 110 or an expanded ROM 115. The components 100-112 are formed into one chip so as to expedite the access speed of the CPU 112 to the built-in ROM 110. An interruption process of high CPU load ratio is stored in the built-in ROM 110, while an operating system, etc., of low CPU load ratio is stored in the expanded ROM 115. |
