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=Timers/Counters in AVR=
 
=Timers/Counters in AVR=
==Timer 0==
+
==Timer 0 ==
 
[[File:Timer 0.png|center]]
 
[[File:Timer 0.png|center]]
 +
===Timer 0 Registers===
 +
====TCNT0: Timer/Counter Register 0====
 
{| class="wikitable floatright" style="float:right; background-color:#3DA8BB;"
 
{| class="wikitable floatright" style="float:right; background-color:#3DA8BB;"
 
!colspan = '8'|TCNT0
 
!colspan = '8'|TCNT0
 
|+Timer/Counter 0
 
|+Timer/Counter 0
 
|D7||D6||D5||D4||D3||D2||D1||D0
 
|D7||D6||D5||D4||D3||D2||D1||D0
 +
|}
 +
 +
====TCCR0: Timer/Counter Control Register====
 +
{| class="wikitable floatright" style="float:right; background-color:#3DA8BB;"
 +
!colspan = '8'|TCCR0
 +
|-
 +
|D7||D6||D5||D4||D3||D2||D1||D0
 +
|-
 +
|FOC0||WGM00||COM01||COM00||WGM01||CS02||CS01||CS00
 
|}
 
|}
  
 
==Timer 1==
 
==Timer 1==
 
==Timer 2==
 
==Timer 2==

Revision as of 12:25, 18 November 2014

Basics

Timer/Counter Unit

Timers come in handy when you want to set some time interval like your alarm. This can be very precise to a few microseconds. Timers/Counters are essential part of any modern MCU. Remember it is the same hardware unit inside the MCU that is used either as Timers or Counter. Timers/counters are an independent unit inside a micro-controller. They basically run independently of what task CPU is performing. Hence they come in very handy, and are primarily used for the following:

  • Internal Timer: As an internal timer the unit, ticks on the oscillator frequency. The oscillator frequency can be directly feed to the timer or it can be pre-scaled. In this mode it used generate precise delays. Or as precise time counting machine.
  • External Counter: In this mode the unit is used to count events on a specific external pin on a MCU.
  • Pulse width Modulation(PWM) Generator: PWM is used in speed control of motors and various other applications.

Timers/Counters in AVR

Timer 0

Timer 0.png

Timer 0 Registers

TCNT0: Timer/Counter Register 0

TCNT0
Timer/Counter 0
D7 D6 D5 D4 D3 D2 D1 D0

TCCR0: Timer/Counter Control Register

TCCR0
D7 D6 D5 D4 D3 D2 D1 D0
FOC0 WGM00 COM01 COM00 WGM01 CS02 CS01 CS00

Timer 1

Timer 2