Title:
SAMPLING CONTROL CIRCUIT AND METHOD FOR INTERRUPTION PROCESS
Document Type and Number:
Japanese Patent JP3088402
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To reduce the current consumption of a microcomputer by first checking whether a process by the microcomputer is necessary or not by hardware based on the input information from a peripheral circuit, and canceling a halt state of the microcomputer to proceed to the process by the microcomputer only when the process by the microcomputer is necessary.
SOLUTION: When checking the operating condition of a peripheral circuit 7, a sampling output signal 6 of a constant pulse width is outputted from a microcomputer 1 in a fixed cycle and then is latched into the microcomputer 1 through the peripheral circuit 7. In the microcomputer 1, it is preliminarily determined at which level of the input signal, a high level or a low level, the interrupt should occur, Only when the sampling output signal 6 coincides with the specification, the interrupt is allowed to occur. The interrupt occurs only when the peripheral circuit 7 requires a process by the microcomputer 1 to cancel a standby state of the microcomputer 1. In the other conditions, the microcomputer 1 is kept at a standby state and therefore the current consumption of the microcomputer 1 can be reduced.
Inventors:
Teruo Ichimura
Application Number:
JP36810198A
Publication Date:
September 18, 2000
Filing Date:
December 24, 1998
Export Citation:
Assignee:
NEC IC Microcomputer System Co., Ltd.
International Classes:
G06F15/78; G06F9/46; G06F9/48; H02J1/00; (IPC1-7): G06F9/46; G06F15/78
Domestic Patent References:
| JP895799A | ||||
| JP1217634A | ||||
| JP59182389A | ||||
| JP2192321A | ||||
| JP64194A |
Attorney, Agent or Firm:
Shiroyuki Hori