Basic Library

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

Standard Library

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

Periodic Operation

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.

Sample Program

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() {
        }