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6466117 Jan 3, 2019
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@PaulStoffregen @tr4nt0r @StoykoDimitrov @oyeb
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/*
* Interrupt and PWM utilities for 16 bit Timer1 on ATmega168/328
* Original code by Jesse Tane for http://labs.ideo.com August 2008
* Modified March 2009 by Jérôme Despatis and Jesse Tane for ATmega328 support
* Modified June 2009 by Michael Polli and Jesse Tane to fix a bug in setPeriod() which caused the timer to stop
* Modified April 2012 by Paul Stoffregen - portable to other AVR chips, use inline functions
* Modified again, June 2014 by Paul Stoffregen - support Teensy 3.x & even more AVR chips
* Modified July 2017 by Stoyko Dimitrov - added support for ATTiny85 except for the PWM functionality
*
*
* This is free software. You can redistribute it and/or modify it under
* the terms of Creative Commons Attribution 3.0 United States License.
* To view a copy of this license, visit http://creativecommons.org/licenses/by/3.0/us/
* or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA.
*
*/
#ifndef TimerOne_h_
#define TimerOne_h_
#if defined(ARDUINO) && ARDUINO >= 100
#include "Arduino.h"
#else
#include "WProgram.h"
#endif
#include "config/known_16bit_timers.h"
#if defined (__AVR_ATtiny85__)
#define TIMER1_RESOLUTION 256UL // Timer1 is 8 bit
#elif defined(__AVR__)
#define TIMER1_RESOLUTION 65536UL // Timer1 is 16 bit
#else
#define TIMER1_RESOLUTION 65536UL // assume 16 bits for non-AVR chips
#endif
// Placing nearly all the code in this .h file allows the functions to be
// inlined by the compiler. In the very common case with constant values
// the compiler will perform all calculations and simply write constants
// to the hardware registers (for example, setPeriod).
class TimerOne
{
#if defined (__AVR_ATtiny85__)
public:
//****************************
// Configuration
//****************************
void initialize(unsigned long microseconds=1000000) __attribute__((always_inline)) {
TCCR1 = _BV(CTC1); //clear timer1 when it matches the value in OCR1C
TIMSK |= _BV(OCIE1A); //enable interrupt when OCR1A matches the timer value
setPeriod(microseconds);
}
void setPeriod(unsigned long microseconds) __attribute__((always_inline)) {
const unsigned long cycles = microseconds * ratio;
if (cycles < TIMER1_RESOLUTION) {
clockSelectBits = _BV(CS10);
pwmPeriod = cycles;
} else
if (cycles < TIMER1_RESOLUTION * 2UL) {
clockSelectBits = _BV(CS11);
pwmPeriod = cycles / 2;
} else
if (cycles < TIMER1_RESOLUTION * 4UL) {
clockSelectBits = _BV(CS11) | _BV(CS10);
pwmPeriod = cycles / 4;
} else
if (cycles < TIMER1_RESOLUTION * 8UL) {
clockSelectBits = _BV(CS12);
pwmPeriod = cycles / 8;
} else
if (cycles < TIMER1_RESOLUTION * 16UL) {
clockSelectBits = _BV(CS12) | _BV(CS10);
pwmPeriod = cycles / 16;
} else
if (cycles < TIMER1_RESOLUTION * 32UL) {
clockSelectBits = _BV(CS12) | _BV(CS11);
pwmPeriod = cycles / 32;
} else
if (cycles < TIMER1_RESOLUTION * 64UL) {
clockSelectBits = _BV(CS12) | _BV(CS11) | _BV(CS10);
pwmPeriod = cycles / 64UL;
} else
if (cycles < TIMER1_RESOLUTION * 128UL) {
clockSelectBits = _BV(CS13);
pwmPeriod = cycles / 128;
} else
if (cycles < TIMER1_RESOLUTION * 256UL) {
clockSelectBits = _BV(CS13) | _BV(CS10);
pwmPeriod = cycles / 256;
} else
if (cycles < TIMER1_RESOLUTION * 512UL) {
clockSelectBits = _BV(CS13) | _BV(CS11);
pwmPeriod = cycles / 512;
} else
if (cycles < TIMER1_RESOLUTION * 1024UL) {
clockSelectBits = _BV(CS13) | _BV(CS11) | _BV(CS10);
pwmPeriod = cycles / 1024;
} else
if (cycles < TIMER1_RESOLUTION * 2048UL) {
clockSelectBits = _BV(CS13) | _BV(CS12);
pwmPeriod = cycles / 2048;
} else
if (cycles < TIMER1_RESOLUTION * 4096UL) {
clockSelectBits = _BV(CS13) | _BV(CS12) | _BV(CS10);
pwmPeriod = cycles / 4096;
} else
if (cycles < TIMER1_RESOLUTION * 8192UL) {
clockSelectBits = _BV(CS13) | _BV(CS12) | _BV(CS11);
pwmPeriod = cycles / 8192;
} else
if (cycles < TIMER1_RESOLUTION * 16384UL) {
clockSelectBits = _BV(CS13) | _BV(CS12) | _BV(CS11) | _BV(CS10);
pwmPeriod = cycles / 16384;
} else {
clockSelectBits = _BV(CS13) | _BV(CS12) | _BV(CS11) | _BV(CS10);
pwmPeriod = TIMER1_RESOLUTION - 1;
}
OCR1A = pwmPeriod;
OCR1C = pwmPeriod;
TCCR1 = _BV(CTC1) | clockSelectBits;
}
//****************************
// Run Control
//****************************
void start() __attribute__((always_inline)) {
TCCR1 = 0;
TCNT1 = 0;
resume();
}
void stop() __attribute__((always_inline)) {
TCCR1 = _BV(CTC1);
}
void restart() __attribute__((always_inline)) {
start();
}
void resume() __attribute__((always_inline)) {
TCCR1 = _BV(CTC1) | clockSelectBits;
}
//****************************
// PWM outputs
//****************************
//Not implemented yet for ATTiny85
//TO DO
//****************************
// Interrupt Function
//****************************
void attachInterrupt(void (*isr)()) __attribute__((always_inline)) {
isrCallback = isr;
TIMSK |= _BV(OCIE1A);
}
void attachInterrupt(void (*isr)(), unsigned long microseconds) __attribute__((always_inline)) {
if(microseconds > 0) setPeriod(microseconds);
attachInterrupt(isr);
}
void detachInterrupt() __attribute__((always_inline)) {
//TIMSK = 0; // Timer 0 and Timer 1 both use TIMSK register so setting it to 0 will override settings for Timer1 as well
TIMSK &= ~_BV(OCIE1A);
}
static void (*isrCallback)();
static void isrDefaultUnused();
private:
static unsigned short pwmPeriod;
static unsigned char clockSelectBits;
static const byte ratio = (F_CPU)/ ( 1000000 );
#elif defined(__AVR__)
#if defined (__AVR_ATmega8__)
//in some io definitions for older microcontrollers TIMSK is used instead of TIMSK1
#define TIMSK1 TIMSK
#endif
public:
//****************************
// Configuration
//****************************
void initialize(unsigned long microseconds=1000000) __attribute__((always_inline)) {
TCCR1B = _BV(WGM13); // set mode as phase and frequency correct pwm, stop the timer
TCCR1A = 0; // clear control register A
setPeriod(microseconds);
}
void setPeriod(unsigned long microseconds) __attribute__((always_inline)) {
const unsigned long cycles = ((F_CPU/100000 * microseconds) / 20);
if (cycles < TIMER1_RESOLUTION) {
clockSelectBits = _BV(CS10);
pwmPeriod = cycles;
} else
if (cycles < TIMER1_RESOLUTION * 8) {
clockSelectBits = _BV(CS11);
pwmPeriod = cycles / 8;
} else
if (cycles < TIMER1_RESOLUTION * 64) {
clockSelectBits = _BV(CS11) | _BV(CS10);
pwmPeriod = cycles / 64;
} else
if (cycles < TIMER1_RESOLUTION * 256) {
clockSelectBits = _BV(CS12);
pwmPeriod = cycles / 256;
} else
if (cycles < TIMER1_RESOLUTION * 1024) {
clockSelectBits = _BV(CS12) | _BV(CS10);
pwmPeriod = cycles / 1024;
} else {
clockSelectBits = _BV(CS12) | _BV(CS10);
pwmPeriod = TIMER1_RESOLUTION - 1;
}
ICR1 = pwmPeriod;
TCCR1B = _BV(WGM13) | clockSelectBits;
}
//****************************
// Run Control
//****************************
void start() __attribute__((always_inline)) {
TCCR1B = 0;
TCNT1 = 0; // TODO: does this cause an undesired interrupt?
resume();
}
void stop() __attribute__((always_inline)) {
TCCR1B = _BV(WGM13);
}
void restart() __attribute__((always_inline)) {
start();
}
void resume() __attribute__((always_inline)) {
TCCR1B = _BV(WGM13) | clockSelectBits;
}
//****************************
// PWM outputs
//****************************
void setPwmDuty(char pin, unsigned int duty) __attribute__((always_inline)) {
unsigned long dutyCycle = pwmPeriod;
dutyCycle *= duty;
dutyCycle >>= 10;
if (pin == TIMER1_A_PIN) OCR1A = dutyCycle;
#ifdef TIMER1_B_PIN
else if (pin == TIMER1_B_PIN) OCR1B = dutyCycle;
#endif
#ifdef TIMER1_C_PIN
else if (pin == TIMER1_C_PIN) OCR1C = dutyCycle;
#endif
}
void pwm(char pin, unsigned int duty) __attribute__((always_inline)) {
if (pin == TIMER1_A_PIN) { pinMode(TIMER1_A_PIN, OUTPUT); TCCR1A |= _BV(COM1A1); }
#ifdef TIMER1_B_PIN
else if (pin == TIMER1_B_PIN) { pinMode(TIMER1_B_PIN, OUTPUT); TCCR1A |= _BV(COM1B1); }
#endif
#ifdef TIMER1_C_PIN
else if (pin == TIMER1_C_PIN) { pinMode(TIMER1_C_PIN, OUTPUT); TCCR1A |= _BV(COM1C1); }
#endif
setPwmDuty(pin, duty);
TCCR1B = _BV(WGM13) | clockSelectBits;
}
void pwm(char pin, unsigned int duty, unsigned long microseconds) __attribute__((always_inline)) {
if (microseconds > 0) setPeriod(microseconds);
pwm(pin, duty);
}
void disablePwm(char pin) __attribute__((always_inline)) {
if (pin == TIMER1_A_PIN) TCCR1A &= ~_BV(COM1A1);
#ifdef TIMER1_B_PIN
else if (pin == TIMER1_B_PIN) TCCR1A &= ~_BV(COM1B1);
#endif
#ifdef TIMER1_C_PIN
else if (pin == TIMER1_C_PIN) TCCR1A &= ~_BV(COM1C1);
#endif
}
//****************************
// Interrupt Function
//****************************
void attachInterrupt(void (*isr)()) __attribute__((always_inline)) {
isrCallback = isr;
TIMSK1 = _BV(TOIE1);
}
void attachInterrupt(void (*isr)(), unsigned long microseconds) __attribute__((always_inline)) {
if(microseconds > 0) setPeriod(microseconds);
attachInterrupt(isr);
}
void detachInterrupt() __attribute__((always_inline)) {
TIMSK1 = 0;
}
static void (*isrCallback)();
static void isrDefaultUnused();
private:
// properties
static unsigned short pwmPeriod;
static unsigned char clockSelectBits;
#elif defined(__arm__) && defined(TEENSYDUINO) && (defined(KINETISK) || defined(KINETISL))
#if defined(KINETISK)
#define F_TIMER F_BUS
#elif defined(KINETISL)
#define F_TIMER (F_PLL/2)
#endif
// Use only 15 bit resolution. From K66 reference manual, 45.5.7 page 1200:
// The CPWM pulse width (duty cycle) is determined by 2 x (CnV - CNTIN) and the
// period is determined by 2 x (MOD - CNTIN). See the following figure. MOD must be
// kept in the range of 0x0001 to 0x7FFF because values outside this range can produce
// ambiguous results.
#undef TIMER1_RESOLUTION
#define TIMER1_RESOLUTION 32768
public:
//****************************
// Configuration
//****************************
void initialize(unsigned long microseconds=1000000) __attribute__((always_inline)) {
setPeriod(microseconds);
}
void setPeriod(unsigned long microseconds) __attribute__((always_inline)) {
const unsigned long cycles = (F_TIMER / 2000000) * microseconds;
// A much faster if-else
// This is like a binary serch tree and no more than 3 conditions are evaluated.
// I haven't checked if this becomes significantly longer ASM than the simple ladder.
// It looks very similar to the ladder tho: same # of if's and else's
/*
// This code does not work properly in all cases :(
// https://github.com/PaulStoffregen/TimerOne/issues/17
if (cycles < TIMER1_RESOLUTION * 16) {
if (cycles < TIMER1_RESOLUTION * 4) {
if (cycles < TIMER1_RESOLUTION) {
clockSelectBits = 0;
pwmPeriod = cycles;
}else{
clockSelectBits = 1;
pwmPeriod = cycles >> 1;
}
}else{
if (cycles < TIMER1_RESOLUTION * 8) {
clockSelectBits = 3;
pwmPeriod = cycles >> 3;
}else{
clockSelectBits = 4;
pwmPeriod = cycles >> 4;
}
}
}else{
if (cycles > TIMER1_RESOLUTION * 64) {
if (cycles > TIMER1_RESOLUTION * 128) {
clockSelectBits = 7;
pwmPeriod = TIMER1_RESOLUTION - 1;
}else{
clockSelectBits = 7;
pwmPeriod = cycles >> 7;
}
}
else{
if (cycles > TIMER1_RESOLUTION * 32) {
clockSelectBits = 6;
pwmPeriod = cycles >> 6;
}else{
clockSelectBits = 5;
pwmPeriod = cycles >> 5;
}
}
}
*/
if (cycles < TIMER1_RESOLUTION) {
clockSelectBits = 0;
pwmPeriod = cycles;
} else
if (cycles < TIMER1_RESOLUTION * 2) {
clockSelectBits = 1;
pwmPeriod = cycles >> 1;
} else
if (cycles < TIMER1_RESOLUTION * 4) {
clockSelectBits = 2;
pwmPeriod = cycles >> 2;
} else
if (cycles < TIMER1_RESOLUTION * 8) {
clockSelectBits = 3;
pwmPeriod = cycles >> 3;
} else
if (cycles < TIMER1_RESOLUTION * 16) {
clockSelectBits = 4;
pwmPeriod = cycles >> 4;
} else
if (cycles < TIMER1_RESOLUTION * 32) {
clockSelectBits = 5;
pwmPeriod = cycles >> 5;
} else
if (cycles < TIMER1_RESOLUTION * 64) {
clockSelectBits = 6;
pwmPeriod = cycles >> 6;
} else
if (cycles < TIMER1_RESOLUTION * 128) {
clockSelectBits = 7;
pwmPeriod = cycles >> 7;
} else {
clockSelectBits = 7;
pwmPeriod = TIMER1_RESOLUTION - 1;
}
uint32_t sc = FTM1_SC;
FTM1_SC = 0;
FTM1_MOD = pwmPeriod;
FTM1_SC = FTM_SC_CLKS(1) | FTM_SC_CPWMS | clockSelectBits | (sc & FTM_SC_TOIE);
}
//****************************
// Run Control
//****************************
void start() __attribute__((always_inline)) {
stop();
FTM1_CNT = 0;
resume();
}
void stop() __attribute__((always_inline)) {
FTM1_SC = FTM1_SC & (FTM_SC_TOIE | FTM_SC_CPWMS | FTM_SC_PS(7));
}
void restart() __attribute__((always_inline)) {
start();
}
void resume() __attribute__((always_inline)) {
FTM1_SC = (FTM1_SC & (FTM_SC_TOIE | FTM_SC_PS(7))) | FTM_SC_CPWMS | FTM_SC_CLKS(1);
}
//****************************
// PWM outputs
//****************************
void setPwmDuty(char pin, unsigned int duty) __attribute__((always_inline)) {
unsigned long dutyCycle = pwmPeriod;
dutyCycle *= duty;
dutyCycle >>= 10;
if (pin == TIMER1_A_PIN) {
FTM1_C0V = dutyCycle;
} else if (pin == TIMER1_B_PIN) {
FTM1_C1V = dutyCycle;
}
}
void pwm(char pin, unsigned int duty) __attribute__((always_inline)) {
setPwmDuty(pin, duty);
if (pin == TIMER1_A_PIN) {
*portConfigRegister(TIMER1_A_PIN) = PORT_PCR_MUX(3) | PORT_PCR_DSE | PORT_PCR_SRE;
} else if (pin == TIMER1_B_PIN) {
*portConfigRegister(TIMER1_B_PIN) = PORT_PCR_MUX(3) | PORT_PCR_DSE | PORT_PCR_SRE;
}
}
void pwm(char pin, unsigned int duty, unsigned long microseconds) __attribute__((always_inline)) {
if (microseconds > 0) setPeriod(microseconds);
pwm(pin, duty);
}
void disablePwm(char pin) __attribute__((always_inline)) {
if (pin == TIMER1_A_PIN) {
*portConfigRegister(TIMER1_A_PIN) = 0;
} else if (pin == TIMER1_B_PIN) {
*portConfigRegister(TIMER1_B_PIN) = 0;
}
}
//****************************
// Interrupt Function
//****************************
void attachInterrupt(void (*isr)()) __attribute__((always_inline)) {
isrCallback = isr;
FTM1_SC |= FTM_SC_TOIE;
NVIC_ENABLE_IRQ(IRQ_FTM1);
}
void attachInterrupt(void (*isr)(), unsigned long microseconds) __attribute__((always_inline)) {
if(microseconds > 0) setPeriod(microseconds);
attachInterrupt(isr);
}
void detachInterrupt() __attribute__((always_inline)) {
FTM1_SC &= ~FTM_SC_TOIE;
NVIC_DISABLE_IRQ(IRQ_FTM1);
}
static void (*isrCallback)();
static void isrDefaultUnused();
private:
// properties
static unsigned short pwmPeriod;
static unsigned char clockSelectBits;
#undef F_TIMER
#elif defined(__arm__) && defined(TEENSYDUINO) && (defined(__IMXRT1052__) || defined(__IMXRT1062__))
public:
//****************************
// Configuration
//****************************
void initialize(unsigned long microseconds=1000000) __attribute__((always_inline)) {
setPeriod(microseconds);
}
void setPeriod(unsigned long microseconds) __attribute__((always_inline)) {
uint32_t period = (float)F_BUS_ACTUAL * (float)microseconds * 0.0000005f;
uint32_t prescale = 0;
while (period > 32767) {
period = period >> 1;
if (++prescale > 7) {
prescale = 7; // when F_BUS is 150 MHz, longest
period = 32767; // period is 55922 us (~17.9 Hz)
break;
}
}
//Serial.printf("setPeriod, period=%u, prescale=%u\n", period, prescale);
FLEXPWM1_FCTRL0 |= FLEXPWM_FCTRL0_FLVL(8); // logic high = fault
FLEXPWM1_FSTS0 = 0x0008; // clear fault status
FLEXPWM1_MCTRL |= FLEXPWM_MCTRL_CLDOK(8);
FLEXPWM1_SM3CTRL2 = FLEXPWM_SMCTRL2_INDEP;
FLEXPWM1_SM3CTRL = FLEXPWM_SMCTRL_HALF | FLEXPWM_SMCTRL_PRSC(prescale);
FLEXPWM1_SM3INIT = -period;
FLEXPWM1_SM3VAL0 = 0;
FLEXPWM1_SM3VAL1 = period;
FLEXPWM1_SM3VAL2 = 0;
FLEXPWM1_SM3VAL3 = 0;
FLEXPWM1_SM3VAL4 = 0;
FLEXPWM1_SM3VAL5 = 0;
FLEXPWM1_MCTRL |= FLEXPWM_MCTRL_LDOK(8) | FLEXPWM_MCTRL_RUN(8);
pwmPeriod = period;
}
//****************************
// Run Control
//****************************
void start() __attribute__((always_inline)) {
stop();
// TODO: how to force counter back to zero?
resume();
}
void stop() __attribute__((always_inline)) {
FLEXPWM1_MCTRL &= ~FLEXPWM_MCTRL_RUN(8);
}
void restart() __attribute__((always_inline)) {
start();
}
void resume() __attribute__((always_inline)) {
FLEXPWM1_MCTRL |= FLEXPWM_MCTRL_RUN(8);
}
//****************************
// PWM outputs
//****************************
void setPwmDuty(char pin, unsigned int duty) __attribute__((always_inline)) {
if (duty > 1023) duty = 1023;
int dutyCycle = (pwmPeriod * duty) >> 10;
//Serial.printf("setPwmDuty, period=%u\n", dutyCycle);
if (pin == TIMER1_A_PIN) {
FLEXPWM1_MCTRL |= FLEXPWM_MCTRL_CLDOK(8);
FLEXPWM1_SM3VAL5 = dutyCycle;
FLEXPWM1_SM3VAL4 = -dutyCycle;
FLEXPWM1_MCTRL |= FLEXPWM_MCTRL_LDOK(8);
} else if (pin == TIMER1_B_PIN) {
FLEXPWM1_MCTRL |= FLEXPWM_MCTRL_CLDOK(8);
FLEXPWM1_SM3VAL3 = dutyCycle;
FLEXPWM1_SM3VAL2 = -dutyCycle;
FLEXPWM1_MCTRL |= FLEXPWM_MCTRL_LDOK(8);
}
}
void pwm(char pin, unsigned int duty) __attribute__((always_inline)) {
setPwmDuty(pin, duty);
if (pin == TIMER1_A_PIN) {
FLEXPWM1_OUTEN |= FLEXPWM_OUTEN_PWMB_EN(8);
IOMUXC_SW_MUX_CTL_PAD_GPIO_B1_01 = 6; // pin 6 FLEXPWM1_PWM3_B
} else if (pin == TIMER1_B_PIN) {
FLEXPWM1_OUTEN |= FLEXPWM_OUTEN_PWMA_EN(8);
IOMUXC_SW_MUX_CTL_PAD_GPIO_B1_00 = 6; // pin 7 FLEXPWM1_PWM3_A
}
}
void pwm(char pin, unsigned int duty, unsigned long microseconds) __attribute__((always_inline)) {
if (microseconds > 0) setPeriod(microseconds);
pwm(pin, duty);
}
void disablePwm(char pin) __attribute__((always_inline)) {
if (pin == TIMER1_A_PIN) {
IOMUXC_SW_MUX_CTL_PAD_GPIO_B1_01 = 5; // pin 6 FLEXPWM1_PWM3_B
FLEXPWM1_OUTEN &= ~FLEXPWM_OUTEN_PWMB_EN(8);
} else if (pin == TIMER1_B_PIN) {
IOMUXC_SW_MUX_CTL_PAD_GPIO_B1_00 = 5; // pin 7 FLEXPWM1_PWM3_A
FLEXPWM1_OUTEN &= ~FLEXPWM_OUTEN_PWMA_EN(8);
}
}
//****************************
// Interrupt Function
//****************************
void attachInterrupt(void (*f)()) __attribute__((always_inline)) {
isrCallback = f;
attachInterruptVector(IRQ_FLEXPWM1_3, &isr);
FLEXPWM1_SM3STS = FLEXPWM_SMSTS_RF;
FLEXPWM1_SM3INTEN = FLEXPWM_SMINTEN_RIE;
NVIC_ENABLE_IRQ(IRQ_FLEXPWM1_3);
}
void attachInterrupt(void (*f)(), unsigned long microseconds) __attribute__((always_inline)) {
if(microseconds > 0) setPeriod(microseconds);
attachInterrupt(f);
}
void detachInterrupt() __attribute__((always_inline)) {
NVIC_DISABLE_IRQ(IRQ_FLEXPWM1_3);
FLEXPWM1_SM3INTEN = 0;
}
static void isr(void);
static void (*isrCallback)();
static void isrDefaultUnused();
private:
// properties
static unsigned short pwmPeriod;
static unsigned char clockSelectBits;
#endif
};
extern TimerOne Timer1;
#endif