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/*! \file timer.h \brief System Timer function library. *///*****************************************************************************//// File Name : 'timer.h'// Title : System Timer function library// Author : Pascal Stang - Copyright (C) 2000-2002// Created : 11/22/2000// Revised : 02/10/2003// Version : 1.1// Target MCU : Atmel AVR Series// Editor Tabs : 4//// This code is distributed under the GNU Public License// which can be found at http://www.gnu.org/licenses/gpl.txt///// \ingroup driver_avr/// \defgroup timer Timer Function Library (timer.c)/// \code #include "timer.h" \endcode/// \par Overview/// This library provides functions for use with the timers internal/// to the AVR processors. Functions include initialization, set prescaler,/// calibrated pause function (in milliseconds), attaching and detaching of/// user functions to interrupts, overflow counters, PWM. Arbitrary/// frequency generation has been moved to the Pulse Library.////// \par About Timers/// The Atmel AVR-series processors each contain at least one/// hardware timer/counter. Many of the processors contain 2 or 3/// timers. Generally speaking, a timer is a hardware counter inside/// the processor which counts at a rate related to the main CPU clock/// frequency. Because the counter value increasing (counting up) at/// a precise rate, we can use it as a timer to create or measure/// precise delays, schedule events, or generate signals of a certain/// frequency or pulse-width./// \par/// As an example, the ATmega163 processor has 3 timer/counters./// Timer0, Timer1, and Timer2 are 8, 16, and 8 bits wide respectively./// This means that they overflow, or roll over back to zero, at a/// count value of 256 for 8bits or 65536 for 16bits. A prescaler is/// avaiable for each timer, and the prescaler allows you to pre-divide/// the main CPU clock rate down to a slower speed before feeding it to/// the counting input of a timer. For example, if the CPU clock/// frequency is 3.69MHz, and Timer0's prescaler is set to divide-by-8,/// then Timer0 will "tic" at 3690000/8 = 461250Hz. Because Timer0 is/// an 8bit timer, it will count to 256 in just 256/461250Hz = 0.555ms./// In fact, when it hits 255, it will overflow and start again at/// zero. In this case, Timer0 will overflow 461250/256 = 1801.76/// times per second./// \par/// Timer0 can be used a number of ways simultaneously. First, the/// value of the timer can be read by accessing the CPU register \c TCNT0./// We could, for example, figure out how long it takes to execute a/// C command by recording the value of \c TCNT0 before and after/// execution, then subtract (after-before) = time elapsed. Or we can/// enable the overflow interrupt which goes off every time T0/// overflows and count out longer delays (multiple overflows), or/// execute a special periodic function at every overflow./// \par/// The other timers (Timer1 and Timer2) offer all the abilities of/// Timer0 and many more features. Both T1 and T2 can operate as/// general-purpose timers, but T1 has special hardware allowing it to/// generate PWM signals, while T2 is specially designed to help count/// out real time (like hours, minutes, seconds). See the/// Timer/Counter section of the processor datasheet for more info./////*****************************************************************************//@{#ifndef TIMER_H#define TIMER_H#include "global.h"// constants/macros/typdefs// processor compatibility fixes#ifdef __AVR_ATmega323__// redefinition for the Mega323#define CTC1 CTC10#endif#ifndef PWM10// mega128 PWM bits#define PWM10 WGM10#define PWM11 WGM11#endif// Timer/clock prescaler values and timer overflow rates// tics = rate at which the timer counts up// 8bitoverflow = rate at which the timer overflows 8bits (or reaches 256)// 16bit [overflow] = rate at which the timer overflows 16bits (65536)//// overflows can be used to generate periodic interrupts//// for 8MHz crystal// 0 = STOP (Timer not counting)// 1 = CLOCK tics= 8MHz 8bitoverflow= 31250Hz 16bit= 122.070Hz// 2 = CLOCK/8 tics= 1MHz 8bitoverflow= 3906.25Hz 16bit= 15.259Hz// 3 = CLOCK/64 tics= 125kHz 8bitoverflow= 488.28Hz 16bit= 1.907Hz// 4 = CLOCK/256 tics= 31250Hz 8bitoverflow= 122.07Hz 16bit= 0.477Hz// 5 = CLOCK/1024 tics= 7812.5Hz 8bitoverflow= 30.52Hz 16bit= 0.119Hz// 6 = External Clock on T(x) pin (falling edge)// 7 = External Clock on T(x) pin (rising edge)// for 4MHz crystal// 0 = STOP (Timer not counting)// 1 = CLOCK tics= 4MHz 8bitoverflow= 15625Hz 16bit= 61.035Hz// 2 = CLOCK/8 tics= 500kHz 8bitoverflow= 1953.125Hz 16bit= 7.629Hz// 3 = CLOCK/64 tics= 62500Hz 8bitoverflow= 244.141Hz 16bit= 0.954Hz// 4 = CLOCK/256 tics= 15625Hz 8bitoverflow= 61.035Hz 16bit= 0.238Hz// 5 = CLOCK/1024 tics= 3906.25Hz 8bitoverflow= 15.259Hz 16bit= 0.060Hz// 6 = External Clock on T(x) pin (falling edge)// 7 = External Clock on T(x) pin (rising edge)// for 3.69MHz crystal// 0 = STOP (Timer not counting)// 1 = CLOCK tics= 3.69MHz 8bitoverflow= 14414Hz 16bit= 56.304Hz// 2 = CLOCK/8 tics= 461250Hz 8bitoverflow= 1801.758Hz 16bit= 7.038Hz// 3 = CLOCK/64 tics= 57625.25Hz 8bitoverflow= 225.220Hz 16bit= 0.880Hz// 4 = CLOCK/256 tics= 14414.063Hz 8bitoverflow= 56.305Hz 16bit= 0.220Hz// 5 = CLOCK/1024 tics= 3603.516Hz 8bitoverflow= 14.076Hz 16bit= 0.055Hz// 6 = External Clock on T(x) pin (falling edge)// 7 = External Clock on T(x) pin (rising edge)// for 32.768KHz crystal on timer 2 (use for real-time clock)// 0 = STOP// 1 = CLOCK tics= 32.768kHz 8bitoverflow= 128Hz// 2 = CLOCK/8 tics= 4096kHz 8bitoverflow= 16Hz// 3 = CLOCK/32 tics= 1024kHz 8bitoverflow= 4Hz// 4 = CLOCK/64 tics= 512Hz 8bitoverflow= 2Hz// 5 = CLOCK/128 tics= 256Hz 8bitoverflow= 1Hz// 6 = CLOCK/256 tics= 128Hz 8bitoverflow= 0.5Hz// 7 = CLOCK/1024 tics= 32Hz 8bitoverflow= 0.125Hz#define TIMER_CLK_STOP 0x00 ///< Timer Stopped#define TIMER_CLK_DIV1 0x01 ///< Timer clocked at F_CPU#define TIMER_CLK_DIV8 0x02 ///< Timer clocked at F_CPU/8#define TIMER_CLK_DIV64 0x03 ///< Timer clocked at F_CPU/64#define TIMER_CLK_DIV256 0x04 ///< Timer clocked at F_CPU/256#define TIMER_CLK_DIV1024 0x05 ///< Timer clocked at F_CPU/1024#define TIMER_CLK_T_FALL 0x06 ///< Timer clocked at T falling edge#define TIMER_CLK_T_RISE 0x07 ///< Timer clocked at T rising edge#define TIMER_PRESCALE_MASK 0x07 ///< Timer Prescaler Bit-Mask#define TIMERRTC_CLK_STOP 0x00 ///< RTC Timer Stopped#define TIMERRTC_CLK_DIV1 0x01 ///< RTC Timer clocked at F_CPU#define TIMERRTC_CLK_DIV8 0x02 ///< RTC Timer clocked at F_CPU/8#define TIMERRTC_CLK_DIV32 0x03 ///< RTC Timer clocked at F_CPU/32#define TIMERRTC_CLK_DIV64 0x04 ///< RTC Timer clocked at F_CPU/64#define TIMERRTC_CLK_DIV128 0x05 ///< RTC Timer clocked at F_CPU/128#define TIMERRTC_CLK_DIV256 0x06 ///< RTC Timer clocked at F_CPU/256#define TIMERRTC_CLK_DIV1024 0x07 ///< RTC Timer clocked at F_CPU/1024#define TIMERRTC_PRESCALE_MASK 0x07 ///< RTC Timer Prescaler Bit-Mask// default prescale settings for the timers// these settings are applied when you call// timerInit or any of the timer<x>Init#define TIMER0PRESCALE TIMER_CLK_DIV8 ///< timer 0 prescaler default#define TIMER1PRESCALE TIMER_CLK_DIV64 ///< timer 1 prescaler default#define TIMER2PRESCALE TIMERRTC_CLK_DIV64 ///< timer 2 prescaler default// interrupt macros for attaching user functions to timer interrupts// use these with timerAttach( intNum, function )#define TIMER0OVERFLOW_INT 0#define TIMER1OVERFLOW_INT 1#define TIMER1OUTCOMPAREA_INT 2#define TIMER1OUTCOMPAREB_INT 3#define TIMER1INPUTCAPTURE_INT 4#define TIMER2OVERFLOW_INT 5#define TIMER2OUTCOMPARE_INT 6#ifdef OCR0 // for processors that support output compare on Timer0#define TIMER0OUTCOMPARE_INT 7#define TIMER_NUM_INTERRUPTS 8#else#define TIMER_NUM_INTERRUPTS 7#endif// default type of interrupt handler to use for timers// *do not change unless you know what you're doing// Value may be SIGNAL or INTERRUPT#ifndef TIMER_INTERRUPT_HANDLER#define TIMER_INTERRUPT_HANDLER SIGNAL#endif// functions#define delay delay_us#define delay_ms timerPausevoid delay_us(unsigned short time_us);//! initializes timing system (all timers)// runs all timer init functions// sets all timers to default prescale values #defined in systimer.cvoid timerInit(void);// default initialization routines for each timervoid timer0Init(void); ///< initialize timer0void timer1Init(void); ///< initialize timer1#ifdef TCNT2 // support timer2 only if it existsvoid timer2Init(void); ///< initialize timer2#endif// Clock prescaler set/get commands for each timer/counter// For setting the prescaler, you should use one of the #defines// above like TIMER_CLK_DIVx, where [x] is the division rate// you want.// When getting the current prescaler setting, the return value// will be the [x] division value currently set.void timer0SetPrescaler(u08 prescale); ///< set timer0 prescaleru16 timer0GetPrescaler(void); ///< get timer0 prescalervoid timer1SetPrescaler(u08 prescale); ///< set timer1 prescaleru16 timer1GetPrescaler(void); ///< get timer0 prescaler#ifdef TCNT2 // support timer2 only if it existsvoid timer2SetPrescaler(u08 prescale); ///< set timer2 prescaleru16 timer2GetPrescaler(void); ///< get timer2 prescaler#endif// TimerAttach and Detach commands// These functions allow the attachment (or detachment) of any user function// to a timer interrupt. "Attaching" one of your own functions to a timer// interrupt means that it will be called whenever that interrupt happens.// Using attach is better than rewriting the actual INTERRUPT() function// because your code will still work and be compatible if the timer library// is updated. Also, using Attach allows your code and any predefined timer// code to work together and at the same time. (ie. "attaching" your own// function to the timer0 overflow doesn't prevent timerPause from working,// but rather allows you to share the interrupt.)//// timerAttach(TIMER1OVERFLOW_INT, myOverflowFunction);// timerDetach(TIMER1OVERFLOW_INT)//// timerAttach causes the myOverflowFunction() to be attached, and therefore// execute, whenever an overflow on timer1 occurs. timerDetach removes the// association and executes no user function when the interrupt occurs.// myOverflowFunction must be defined with no return value and no arguments://// void myOverflowFunction(void) { ... }//! Attach a user function to a timer interruptvoid timerAttach(u08 interruptNum, void (*userFunc)(void) );//! Detach a user function from a timer interruptvoid timerDetach(u08 interruptNum);// timing commands/// A timer-based delay/pause function/// @param pause_ms Number of integer milliseconds to wait.void timerPause(unsigned short pause_ms);// overflow countersvoid timer0ClearOverflowCount(void); ///< Clear timer0's overflow counter.long timer0GetOverflowCount(void); ///< read timer0's overflow counter#ifdef TCNT2 // support timer2 only if it existsvoid timer2ClearOverflowCount(void); ///< clear timer2's overflow counterlong timer2GetOverflowCount(void); ///< read timer0's overflow counter#endif/// @defgroup timerpwm Timer PWM Commands/// @ingroup timer/// These commands control PWM functionality on timer1// PWM initialization and set commands for timer1// timer1PWMInit()// configures the timer1 hardware for PWM mode on pins OC1A and OC1B.// bitRes should be 8,9,or 10 for 8,9,or 10bit PWM resolution//// timer1PWMOff()// turns off all timer1 PWM output and set timer mode to normal state//// timer1PWMAOn() and timer1PWMBOn()// turn on output of PWM signals to OC1A or OC1B pins// NOTE: Until you define the OC1A and OC1B pins as outputs, and run// this "on" command, no PWM output will be output//// timer1PWMAOff() and timer1PWMBOff()// turn off output of PWM signals to OC1A or OC1B pins//// timer1PWMASet() and timer1PWMBSet()// sets the PWM duty cycle for each channel// NOTE: <pwmDuty> should be in the range 0-255 for 8bit PWM// <pwmDuty> should be in the range 0-511 for 9bit PWM// <pwmDuty> should be in the range 0-1023 for 10bit PWM// NOTE: the PWM frequency can be controlled in increments by setting the// prescaler for timer1//@{/// Enter standard PWM Mode on timer1./// \param bitRes indicates the period/resolution to use for PWM output in timer bits./// Must be either 8, 9, or 10 bits corresponding to PWM periods of 256, 512, or 1024 timer tics.void timer1PWMInit(u08 bitRes);/// Enter PWM Mode on timer1 with a specific top-count value./// \param topcount indicates the desired PWM period in timer tics./// Can be a number between 1 and 65535 (16-bit).void timer1PWMInitICR(u16 topcount);/// Turn off all timer1 PWM output and set timer mode to normal.void timer1PWMOff(void);/// Turn on/off Timer1 PWM outputs.void timer1PWMAOn(void); ///< Turn on timer1 Channel A (OC1A) PWM output.void timer1PWMBOn(void); ///< Turn on timer1 Channel B (OC1B) PWM output.void timer1PWMAOff(void); ///< turn off timer1 Channel A (OC1A) PWM outputvoid timer1PWMBOff(void); ///< turn off timer1 Channel B (OC1B) PWM outputvoid timer1PWMASet(u16 pwmDuty); ///< set duty of timer1 Channel A (OC1A) PWM outputvoid timer1PWMBSet(u16 pwmDuty); ///< set duty of timer1 Channel B (OC1B) PWM output//@}//@}// Pulse generation commands have been moved to the pulse.c library#endif