Periodic Operation

Digital I/O
Analog I/O
Advanced I/O
Time
Math
Trigonometry
Random Numbers
Bits and Bytes
Interrupts
Communication

Servo Motor
Stepper
Liquid Crystal
EEPROM
SPI
I²C (Wire)
SD Card
SD Card (File Control)
Ethernet
Ethernet (Server)
Ethernet (Client)
Firmata
Periodic Operation
Power Save
Clock (RTC)
SoftwareSerial
Utility

This library allows users to call a function periodically. 4 types of timers are prepared. MsTimer2, one of the types, is compatible with Arduino Uno described in Arduino Playground. It is necessary to specify #include <MsTimer2.h> for using MsTimer2.

attachIntervalTimerHandler

Description

Specifies a call back function executed in the interval timer interrupt handler. The specified call back function is called every 1ms of the interval timer interrupt once it's attached.

Syntax

attachIntervalTimerHandler(void(*)(unsigned long) function)

Parameters

function: Name of the handler

Returns

None

Remark

The following libraries can be called in the handler:
pinMode(), digitalWrite(), digitalRead(), millis(), micros(), delayMicroseconds(), min(), max(), constrain(), map(), lowByte(), highByte(), bitRead(), bitWrite(), bitSet(), bitClear(), bit(), randomSeed(), random()
Note: pinMode(), digitalWrite() may use the pins that are used in function loop(), which may cause a misoperation.

detachIntervalTimerHandler

Description

Turns off the call back function in the interval timer interrupt handler.

Syntax

detachIntervalTimerHandler()

Parameters

None

Returns

None

attachMicroIntervalTimerHandler

Description

Specifies a call back function executed in the interval timer interrupt handler. The specified call back function is called in time specified parameter[us].

Syntax

attachIntervalTimerHandler(void(*)(unsigned long) function, uint16_t interval)

Parameters

function: Name of the handler
interval: Interval time[us]

Returns

None

Remark

The following libraries can be called in the handler:
pinMode(), digitalWrite(), digitalRead(), millis(), micros(), delayMicroseconds(), min(), max(), constrain(), map(), lowByte(), highByte(), bitRead(), bitWrite(), bitSet(), bitClear(), bit(), randomSeed(), random()
Note: pinMode(), digitalWrite() may use the pins that are used in function loop(), which may causes a mis-operation.
tone() is disabled after setting a function. Modify HOOK_TIMER_CHANNEL when you want to change from tone().

MsTimer2::set

Description

Specifies a call back function executed in the specified interval timer interrupt handler.

Syntax

MsTimer2::set(unsigned long ms, void (*function)())

Parameters

ms: Interval(ms)
function: Function name

Returns

None

Notes

The handler is executed by disabled interrupt. In case of executing with use of interrupt, permit an interrupt by interrupt().

MsTimer2::start

Description

Start the timer after set

Syntax

MsTimer2::start()

Parameters

None

Returns

None

MsTimer2::stop

Description

Stop the timer

Syntax

MsTimer2::stop()

Parameters

None

Returns

None

detachIntervalTimerHandler

Description

Turns off the call back function in the interval timer interrupt handler.

Syntax

detachIntervalTimerHandler()

Parameters

None

Returns

None

attachCyclicHandler

Description

Specifies a cyclic call back function. The specified call back function is called at the cycle specified by this function.

Syntax

attachCyclicHandler(unsigned char number, void(*)(unsigned long) function, unsigned int time)

Parameters

number: ID (0 to 7)
function: Function of the interval timer interrupt
time: Interval time in ms

Returns

None

detachCyclicHandler

Description

Turns off the interval call back function.

Syntax

detachCyclicHandler(unsigned char number)

Parameters

number: ID (0 to 7)

Returns

None

Note

The cyclic handler is executed in a loop.

This sample tries to use both the 1ms periodic function and MsTimer2

        #include <Arduino.h>
        #include <MsTimer2.h>
        void using_mstimer2() {
          static boolean output = HIGH;
          
          digitalWrite(12, output);
          output = !output;
        }
          
        // this function is called every 1ms.
        void using_intervaltimer(unsigned long ms){
          static boolean output = HIGH;
          static unsigned long time;
          
          if((ms - time) > 1000){
              interrupts(); // to allow USB operation
              Serial.println(ms);
              time = ms;
              digitalWrite(13, output);
              output = !output;
          }
        }
          
        void setup() {
            pinMode(12, OUTPUT);
            pinMode(13, OUTPUT);
            Serial.begin(9600);
          
          MsTimer2::set(500, using_mstimer2); // 500ms period
          MsTimer2::start();
          
          attachIntervalTimerHandler(using_intervaltimer);
        }
          
        void loop() {
        }