CN202210219U

CN202210219U - Digital stopwatch

Info

Publication number: CN202210219U
Application number: CN2011203085713U
Authority: CN
Inventors: 崔业梅
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-08-23
Filing date: 2011-08-23
Publication date: 2012-05-02
Anticipated expiration: 2021-08-23

Abstract

The utility model discloses a digital stopwatch, which comprises a counting circuit, a display circuit, a counting control circuit and a key circuit. The counting circuit provides enable signals for the key circuit, the key circuit sends counting starting signals, counting stopping signals and counting reset signals to the counting control circuit, and the counting control circuit generates clear pulse and enable pulse to control a timing circuit to start timing, stop timing and reset timing. The display circuit displays a timing result of a timing circuit. The digital stopwatch has the advantages of being reliable in system working, strong in anti-disturbance performance, simple in hardware circuit, clear in program structure and the like.

Description

A kind of digital stopwatch

Technical field

The utility model relates to a kind of timing tool, specifically belongs to the digital circuit technique field.

Background technology

Along with development of electronic technology, electronic technology in the application of every field also more and more widely.People also progressively deepen his understanding, and people have also utilized electronic technology and relevant knowledge to solve some practical problemss.As: the design and fabrication of stopwatch.Stopwatch is a kind of indispensable time set commonly used in the athletic competition, and it is a kind of typical digital circuit.

Stopwatch is a kind of common timing tool, and kind is many.With a kind of digital stopwatch of electronics technical design, can the dirigibility that is beyond one's reach of traditional manufacturing technology be provided for the user, can shorten manufacturing time and reduce manufacturing cost, brought huge time benefit and economic benefit, be the leap of electronic technology.Usually the electronic technology of indication is primarily aimed at design of electronic circuits, PCB design and IC design.

Summary of the invention

The utility model technical matters to be solved is to traditional stopwatch manufacturing technology very flexible, makes low, the defect of high cost of efficient, and a kind of digital stopwatch is provided.

The utility model adopts following technical scheme for solving the problems of the technologies described above:

A kind of digital stopwatch comprises: counting circuit, display circuit, count control circuit, key circuit;

Said counting circuit is that key circuit provides enable signal; Key circuit sends the beginning count signal, stops count signal, reset count signal to count control circuit, and count control circuit produces respectively that quenching pulse, enabling pulse control counting circuit pick up counting, stop timing, timing resets;

Said display circuit is used to show the timing result of counting circuit.

In the said digital stopwatch, counting circuit is made up of clock, frequency divider, 1/100 second digit counter, 1/10 second digit counter, second counter, minute counter, hour counter.

In the said digital stopwatch, key circuit by reset circuit, open/the power failure road, the button debouncing circuit forms, wherein reset circuit, open/the power failure road is connected with the button debouncing circuit respectively.

In the said digital stopwatch, second counter, minute counter, hour counter comprise a decade counter, a sextuple denotation counter respectively.The utility model adopts above technical scheme, has following technique effect:

The utility model adopts the electronic technology design, has advantages such as system works is reliable and stable, strong anti-interference performance, hardware circuit is simple, program structure is distinct.

The digital stopwatch of the utility model contains the button debouncing circuit simultaneously; Accuracy of timekeeping was greater than 0.01 second, and the longest timing time is 24 hours; Timer ability indication range 0.01 second-23: 59: 59.99, figure place showing is 8; Reset key with rise/stop button the inside dithering process that disappears arranged.

Description of drawings

Fig. 1 is the digital stopwatch structural drawing of the utility model.

Embodiment

Below in conjunction with accompanying drawing the technical scheme of the utility model is done further detailed description:

As shown in Figure 1, a kind of digital stopwatch comprises compositions such as counting circuit, display circuit, count control circuit, button debouncing circuit.Counting circuit comprises compositions such as clock, frequency divider, decade counter, sextuple denotation counter again.The button debouncing circuit comprises reset key again, open/stop button and button removes compositions such as shake.

Counting circuit is the main body of stopwatch, and divider circuit obtains count signal with benchmark high frequency frequency division, and reference frequency is high more, and the signal accuracy that obtains behind the frequency division is high more; Sextuple denotation counter and decade counter all are with clear terminal, Enable Pin and carry output; Display circuit is sent in counter output, every group when being respectively ten, the time position, divide ten, divide a position, an individual position, second ten, seconds, 1/10 second position, 1/100 second position; Count control circuit produces quenching pulse and enabling pulse, removes to control decade counter and sextuple denotation counter; System counts also requires to stop when resetting, and promptly quenching pulse also will make enable signal get into low level when making counter O reset, make counter stop counting; The button debouncing circuit, reset signal is obtained by reset key, and enable signal obtains by rise/stopping button, and button is pressed to low flat, if will obtain high level pulse, only needs negate to get final product once; Because button is a Mechanical Contact, may the company of being taken as handle down when clicking by many, so internal control circuit is not usually directly sent in the push button signalling pulse, only produce a pulse but make button once press assurance through debouncing circuit.Reset key is pressed, and with output low level, but owing to the shake reason, several shake pulses after key is pressed, may occur.If design makes button press lasting 3 clock period of counting of back and just exports a monopulse, and if button is pressed the duration greater than 3 clock period, also only exports a monopulse, so promptly eliminate and to avoid key jitter; It is identical therewith to go to shake the method that obtains enable signal through button.

Claims

1. a digital stopwatch is characterized in that comprising: counting circuit, display circuit, count control circuit, key circuit;

Said display circuit is used to show the timing result of counting circuit.

2. digital stopwatch according to claim 1 is characterized in that: said counting circuit is made up of clock, frequency divider, 1/100 second digit counter, 1/10 second digit counter, second counter, minute counter, hour counter.

3. digital stopwatch according to claim 1 is characterized in that: said key circuit by reset circuit, open/the power failure road, the button debouncing circuit forms, wherein reset circuit, open/the power failure road is connected with the button debouncing circuit respectively.

4. digital stopwatch according to claim 2 is characterized in that: counter, minute counter, hour counter comprised a decade counter, a sextuple denotation counter respectively in said second.