Frequency measurement method and apparatus

A technology of frequency measurement and frequency value, which is applied in the field of frequency measurement methods and devices, can solve problems such as multiple external hardware circuits, and achieve the effect of disconnection detection and high-precision frequency measurement

CN101221200AInactive Publication Date: 2008-07-16北京英华达电力电子工程科技有限公司
1 Cites 25 Cited by

Patent Information

Authority / Receiving Office
CN · China
Current Assignee / Owner
Publication Date
2008-07-16
Estimated Expiration
Not applicable · inactive patent

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention discloses a frequency measurement method which comprises the following steps of: receiving a measured signal, the edge of which is used for triggering interrupt; acquiring required sampling times according to current interrupt times when finishing sampling; acquiring sampling time according to times of timer interruption and time of a timer; acquiring frequency value of the measured signal according to the required sampling times and the sampling time. The invention further discloses a frequency measurement device. The invention leads the measured signal to trigger interrupt when sampling, and acquires the frequency value of the measured signal according to the current interrupt times and the sampling time when finishing sampling, thus implementing the high-precision frequency measurement of the measured signal under the situations with less hardware resources used; and the frequency measurement method and the device can implement the functions of off-line detection and conflict-free sharing protection of the data in a main program and an interrupt program.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention relates to the technical field of electronic measurement, in particular to a frequency measurement method and device. Background technique

[0002] At present, the frequency of the signal under test is usually measured by the period measurement method or the frequency measurement method. The period measurement method is to count the reference clock within one period of the signal under test to obtain the period of the signal under test, and then calculate the frequency of the signal under test. When using this method, the measurement accuracy depends on the period of the measured signal and the accuracy of the reference clock, especially when the measured signal is high-frequency, the counting requirements of the reference clock are very high, so this method is more suitable for the measurement of low-frequency signals.

[0003] The frequency measurement method counts the pulses of the signal under test within a certain period of time, a...

Examples

Embodiment Construction

[0021] The specific implementation manners of the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0022] In the embodiment of the present invention, the measured signal is connected to the external interrupt I / O port of the single-chip microcomputer or the microprocessor, and an internal timer of the single-chip microcomputer or the microprocessor is used, without occupying external related hardware circuits and having I / O The port line or resource of the timer / counter of the O port.

[0023] The flow process of a kind of frequency measuring method of the embodiment of the present invention is as shown in Figure 1, in the present embodiment, the single-chip microcomputer adopts the common 51 series of pins and 2051 with few functions (Duojia company can produce compati...