Home
✔ 뷰어로 보기
Pi
2016.10.25 11:46

[Arduino] Timer 라이브러리 사용하기

조회 수 15753 댓글 0
?

단축키

Prev이전 문서

Next다음 문서

가 + - Up Down Comment Print
?

단축키

Prev이전 문서

Next다음 문서

가 + - Up Down Comment Print

http://playground.arduino.cc/Code/Timer


Navigation

Information

Description

Similar to SimpleTimer, which I discovered after writing this library, this library also allows control of pins in a similar way to Metro, so I guess its a bit like a fusion of the two.

The library does not interfere with the built-in timers, it just uses 'millis()' in a crude type of scheduler to decide when something needs doing.

Examples

The Arduino 'delay' function is both a blessing and a curse. Its great for showing beginners how to make an LED flash. But as soon as you get more complex and start slowing down your 'loop' function you will run into problems.

A classic example is turning a relay on for 10 minutes. The 'delay'-way looks like this:

  1. int pin = 13;
  2.  
  3.  
  4. void setup()
  5. {
  6.   pinMode(13, OUTPUT);
  7.   digitalWrite(pin, HIGH);
  8.   delay(10 * 60 * 1000);
  9.   digitalWrite(pin, LOW);
  10. }
  11.  
  12.  
  13. void loop()
  14. {
  15. }
[Get Code]

The disadvantage of the delay approach is that nothing else can go on while the 'delay' is happening. You cannot update a display, or check for key presses for example.

My 'Timer' library version looks like this:

  1. #include "Timer.h"
  2.  
  3.  
  4. Timer t;
  5. int pin = 13;
  6.  
  7.  
  8. void setup()
  9. {
  10.   pinMode(pin, OUTPUT);
  11.   t.pulse(pin, 10 * 60 * 1000, HIGH); // 10 minutes  
  12. }
  13.  
  14.  
  15. void loop()
  16. {
  17.   t.update();
  18. }
[Get Code]

The 'pulse' method takes arguments of a pin to change, the period to change it for and its initial state.

The call to t.update() will take a matter of microseconds to run, unless the appropriate period of time has passed.

Lets look at another example that uses two timer events. One to flash an LED and another that reads A0 and displays the result in the Serial Monitor.

  1. #include "Timer.h"
  2.  
  3.  
  4. Timer t;
  5. int pin = 13;
  6.  
  7.  
  8. void setup()
  9. {
  10.   Serial.begin(9600);
  11.   pinMode(pin, OUTPUT);
  12.   t.oscillate(pin, 100, LOW);
  13.   t.every(1000, takeReading);
  14. }
  15.  
  16.  
  17. void loop()
  18. {
  19.   t.update();
  20. }
  21.  
  22.  
  23. void takeReading()
  24. {
  25.   Serial.println(analogRead(0));
  26. }
[Get Code]

The first thing to notice is that we are using a callback function called 'takeReading'. We connect it to the Timer using the 'every' command, which in this case, will call the function every second.

We have also attached another event to the timer using the method 'oscillate'. This will cause the LED to toggle state every 100 milliseconds.

Each of the events has an integer ID associated with it, so that you can stop an event, as we do in this example below, which will write to the serial monitor every 2 seconds, flash the LED and after 5 seconds, stop the LED flashing fast, and flash it 5 times slowly.

  1. #include "Timer.h"
  2.  
  3.  
  4. Timer t;
  5.  
  6.  
  7. int ledEvent;
  8.  
  9.  
  10. void setup()
  11. {
  12.   Serial.begin(9600);
  13.   int tickEvent = t.every(2000, doSomething);
  14.   Serial.print("2 second tick started id=");
  15.   Serial.println(tickEvent);
  16.  
  17.   pinMode(13, OUTPUT);
  18.   ledEvent = t.oscillate(13, 50, HIGH);
  19.   Serial.print("LED event started id=");
  20.   Serial.println(ledEvent);
  21.  
  22.   int afterEvent = t.after(10000, doAfter);
  23.   Serial.print("After event started id=");
  24.   Serial.println(afterEvent);
  25.  
  26. }
  27.  
  28.  
  29. void loop()
  30. {
  31.   t.update();
  32. }
  33.  
  34.  
  35. void doSomething()
  36. {
  37.   Serial.print("2 second tick: millis()=");
  38.   Serial.println(millis());
  39. }
  40.  
  41.  
  42. void doAfter()
  43. {
  44.   Serial.println("stop the led event");
  45.   t.stop(ledEvent);
  46.   t.oscillate(13, 500, HIGH, 5);
  47. }
[Get Code]

You can attach up to 10 events to a timer.

Installation

You can download the library from here:

https://github.com/JChristensen/Timer

As with all libraries, unzip the file into the 'libraries' folder in your Arduino directory, which will be in something like 'My Documents\Arduino' on Windows, 'Documents/Arduino' on Mac etc. If this is the first library you have installed, you will need to create a directory there called 'libraries'.

The library is compatible with both Arduino 1.0 and earlier versions.

Usage

int every(long period, callback)

 Run the 'callback' every 'period' milliseconds.
 Returns the ID of the timer event.

int every(long period, callback, int repeatCount)

 Run the 'callback' every 'period' milliseconds for a total of 'repeatCount' times.
 Returns the ID of the timer event.

int after(long duration, callback)

 Run the 'callback' once after 'period' milliseconds.
 Returns the ID of the timer event.

int oscillate(int pin, long period, int startingValue)

 Toggle the state of the digital output 'pin' every 'period' milliseconds. The pin's starting value is specified in 'startingValue', which should be HIGH or LOW.
 Returns the ID of the timer event.

int oscillate(int pin, long period, int startingValue, int repeatCount)

 Toggle the state of the digital output 'pin' every 'period' milliseconds 'repeatCount' times. The pin's starting value is specified in 'startingValue', which should be HIGH or LOW.
 Returns the ID of the timer event.

int pulse(int pin, long period, int startingValue)

 Toggle the state of the digital output 'pin' just once after 'period' milliseconds. The pin's starting value is specified in 'startingValue', which should be HIGH or LOW.
 Returns the ID of the timer event.

int stop(int id)

 Stop the timer event running.
 Returns the ID of the timer event.

int update()

 Must be called from 'loop'. This will service all the events associated with the timer.

Links

See also my blog entry on using this library: http://srmonk.blogspot.com/2012/01/arduino-timer-library.html

Trackback http://www.dreamy.pe.kr/zbxe/3768817/7c6/trackback
목록
Up위로 Down아래로 Print인쇄
●? 에디터 선택하기
?

Dreamy의 코드 스크랩

내가 모으고 내가 보는

List of Articles
번호 분류 제목 날짜 조회 수 추천 수
390 Pi NodeMCU PIN 정보 file 2017.01.09 10847 0
389 Pi SD Memory 카드 SPI 3.3V/5.0V 인터페이스 모듈 Atmega2560 제어 예제 2016.12.27 8543 0
388 Pi ATTINY85 PIN정보, Data sheet 2 file 2016.12.10 10994 0
387 Pi 키르히호프의 법칙 2016.12.05 12442 0
386 Pi 아두이노 레오나르도 보드 기본 사용법 2016.11.22 13770 0
385 Pi ARDUINO multi function shield 핀정보 및 FND 소스 2016.11.21 9372 0
384 Pi 시프트 레지스터 사용방법 (Shift Register, 74HC595, 74HC165) 2016.11.21 33472 0
383 Pi 커패시터 용량, 오차 및 정격전압 판별법 (Capacitor Code) file 2016.11.21 17687 0
382 Pi Simple DAC - PWM을 Voltage로 변환하는 회로 file 2016.11.21 9326 0
381 일반 18650 리튬이온 배터리 2016.11.15 24785 0
380 Pi 아두이노 (Arduino) 소개 및 유형별 종류, 제품별 특징 2016.11.15 8710 0
379 Pi 부품 구매 2016.11.15 7754 0
378 Android git 기초 - 원격 저장소 만들고 로그인하기, 소스 되돌리기 2016.10.29 13265 0
377 Pi [Arduino] millis() 함수로 시간 재기 2016.10.25 11674 0
» Pi [Arduino] Timer 라이브러리 사용하기 2016.10.25 15753 0
목록
태그 쓰기
Board Pagination ‹ Prev 1 ... 4 5 6 7 8 9 10 11 12 13 ... 34 Next ›
/ 34

나눔글꼴 설치 안내


이 PC에는 나눔글꼴이 설치되어 있지 않습니다.

이 사이트를 나눔글꼴로 보기 위해서는
나눔글꼴을 설치해야 합니다.

✔ 설치 취소

Designed by sketchbooks.co.kr / sketchbook5 board skin

Sketchbook5, 스케치북5

Sketchbook5, 스케치북5

Sketchbook5, 스케치북5

Sketchbook5, 스케치북5