StartTimer

Syntax:

    StartTimer TimerNo

Command Availability:

Available on all microcontrollers with a Timer module.

Explanation:

StartTimer is used to start the specified timer.

Timer 0:

Please refer to the datasheet to determine if Timer 0 on specific Microchip PIC microcontroller can be started and stopped with starttimer and stoptimer. If the Microchip PIC microcontroller has a register named "T0CON" then it supports stoptimer and starttimer.

On Microchip PIC 18(L)Fxxx microcontrollers Timer 0 can be started with starttimer.
On Microchip PIC baseline and midrange microcontrollers starttimer (and stoptimer) has no effect upon Timer 0.




Example:

This example will measure that time that a switch is depressed (or on) and will write the results to the EEPROM.

    #chip 16F819, 20
    #define SWITCH PORTA.0

    Dir SWITCH In
    DataCount = 0

    'Initilise Timer 1
    InitTimer1 Osc, PS1_8

    Dim TimerValue As Word

    Do
        ClearTimer 1
        Wait Until SWITCH = On
        StartTimer 1          ' <<< the StartTimer instruction
        Wait Until SWITCH = Off
        StopTimer 1

        'Read the timer
        TimerValue = Timer1

        'Log the timer value
        EPWrite(DataCount, TimerValue_H)
        EPWrite(DataCount + 1, TimerValue)
        DataCount += 2
    Loop

Key line: StartTimer 1 — starts Timer 1 counting from wherever ClearTimer left it, right when the switch is pressed.

See Also:

  • InitTimer1 — configuring the timer’s clock source/prescaler before starting it
  • StopTimer / ClearTimer — stopping and resetting the timer, as used above
  • Settimer — preloading a timer’s count value
  • Reading Timers — reading a running timer’s current count
  • EPWrite — logging the measured timer value, as used above

Supported in <TIMER.H>

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