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Adding in clean copies of Servo library from Arduino 1.0.4

Gord Christmas 12 years ago
parent
commit
b668cb0516
2 changed files with 463 additions and 0 deletions
  1. 337
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      Marlin/Servo.cpp
  2. 126
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      Marlin/Servo.h

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Marlin/Servo.cpp View File

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+/*
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+ Servo.cpp - Interrupt driven Servo library for Arduino using 16 bit timers- Version 2
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+ Copyright (c) 2009 Michael Margolis.  All right reserved.
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+
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+ This library is free software; you can redistribute it and/or
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+ modify it under the terms of the GNU Lesser General Public
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+ License as published by the Free Software Foundation; either
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+ version 2.1 of the License, or (at your option) any later version.
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+
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+ This library is distributed in the hope that it will be useful,
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+ but WITHOUT ANY WARRANTY; without even the implied warranty of
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+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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+ Lesser General Public License for more details.
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+
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+ You should have received a copy of the GNU Lesser General Public
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+ License along with this library; if not, write to the Free Software
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+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
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+ */
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+
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+/*
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+
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+ A servo is activated by creating an instance of the Servo class passing the desired pin to the attach() method.
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+ The servos are pulsed in the background using the value most recently written using the write() method
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+
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+ Note that analogWrite of PWM on pins associated with the timer are disabled when the first servo is attached.
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+ Timers are seized as needed in groups of 12 servos - 24 servos use two timers, 48 servos will use four.
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+
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+ The methods are:
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+
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+ Servo - Class for manipulating servo motors connected to Arduino pins.
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+
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+ attach(pin )  - Attaches a servo motor to an i/o pin.
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+ attach(pin, min, max  ) - Attaches to a pin setting min and max values in microseconds
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+ default min is 544, max is 2400
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+
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+ write()     - Sets the servo angle in degrees.  (invalid angle that is valid as pulse in microseconds is treated as microseconds)
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+ writeMicroseconds() - Sets the servo pulse width in microseconds
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+ read()      - Gets the last written servo pulse width as an angle between 0 and 180.
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+ readMicroseconds()   - Gets the last written servo pulse width in microseconds. (was read_us() in first release)
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+ attached()  - Returns true if there is a servo attached.
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+ detach()    - Stops an attached servos from pulsing its i/o pin.
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+
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+*/
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+
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+#include <avr/interrupt.h>
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+#include <Arduino.h>
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+
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+#include "Servo.h"
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+
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+#define usToTicks(_us)    (( clockCyclesPerMicrosecond()* _us) / 8)     // converts microseconds to tick (assumes prescale of 8)  // 12 Aug 2009
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+#define ticksToUs(_ticks) (( (unsigned)_ticks * 8)/ clockCyclesPerMicrosecond() ) // converts from ticks back to microseconds
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+
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+
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+#define TRIM_DURATION       2                               // compensation ticks to trim adjust for digitalWrite delays // 12 August 2009
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+
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+//#define NBR_TIMERS        (MAX_SERVOS / SERVOS_PER_TIMER)
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+
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+static servo_t servos[MAX_SERVOS];                          // static array of servo structures
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+static volatile int8_t Channel[_Nbr_16timers ];             // counter for the servo being pulsed for each timer (or -1 if refresh interval)
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+
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+uint8_t ServoCount = 0;                                     // the total number of attached servos
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+
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+
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+// convenience macros
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+#define SERVO_INDEX_TO_TIMER(_servo_nbr) ((timer16_Sequence_t)(_servo_nbr / SERVOS_PER_TIMER)) // returns the timer controlling this servo
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+#define SERVO_INDEX_TO_CHANNEL(_servo_nbr) (_servo_nbr % SERVOS_PER_TIMER)       // returns the index of the servo on this timer
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+#define SERVO_INDEX(_timer,_channel)  ((_timer*SERVOS_PER_TIMER) + _channel)     // macro to access servo index by timer and channel
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+#define SERVO(_timer,_channel)  (servos[SERVO_INDEX(_timer,_channel)])            // macro to access servo class by timer and channel
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+
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+#define SERVO_MIN() (MIN_PULSE_WIDTH - this->min * 4)  // minimum value in uS for this servo
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+#define SERVO_MAX() (MAX_PULSE_WIDTH - this->max * 4)  // maximum value in uS for this servo
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+
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+/************ static functions common to all instances ***********************/
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+
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+static inline void handle_interrupts(timer16_Sequence_t timer, volatile uint16_t *TCNTn, volatile uint16_t* OCRnA)
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+{
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+  if( Channel[timer] < 0 )
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+    *TCNTn = 0; // channel set to -1 indicated that refresh interval completed so reset the timer
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+  else{
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+    if( SERVO_INDEX(timer,Channel[timer]) < ServoCount && SERVO(timer,Channel[timer]).Pin.isActive == true )
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+      digitalWrite( SERVO(timer,Channel[timer]).Pin.nbr,LOW); // pulse this channel low if activated
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+  }
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+
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+  Channel[timer]++;    // increment to the next channel
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+  if( SERVO_INDEX(timer,Channel[timer]) < ServoCount && Channel[timer] < SERVOS_PER_TIMER) {
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+    *OCRnA = *TCNTn + SERVO(timer,Channel[timer]).ticks;
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+    if(SERVO(timer,Channel[timer]).Pin.isActive == true)     // check if activated
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+      digitalWrite( SERVO(timer,Channel[timer]).Pin.nbr,HIGH); // its an active channel so pulse it high
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+  }
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+  else {
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+    // finished all channels so wait for the refresh period to expire before starting over
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+    if( ((unsigned)*TCNTn) + 4 < usToTicks(REFRESH_INTERVAL) )  // allow a few ticks to ensure the next OCR1A not missed
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+      *OCRnA = (unsigned int)usToTicks(REFRESH_INTERVAL);
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+    else
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+      *OCRnA = *TCNTn + 4;  // at least REFRESH_INTERVAL has elapsed
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+    Channel[timer] = -1; // this will get incremented at the end of the refresh period to start again at the first channel
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+  }
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+}
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+
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+#ifndef WIRING // Wiring pre-defines signal handlers so don't define any if compiling for the Wiring platform
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+// Interrupt handlers for Arduino
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+#if defined(_useTimer1)
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+SIGNAL (TIMER1_COMPA_vect)
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+{
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+  handle_interrupts(_timer1, &TCNT1, &OCR1A);
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+}
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+#endif
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+
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+#if defined(_useTimer3)
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+SIGNAL (TIMER3_COMPA_vect)
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+{
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+  handle_interrupts(_timer3, &TCNT3, &OCR3A);
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+}
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+#endif
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+
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+#if defined(_useTimer4)
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+SIGNAL (TIMER4_COMPA_vect)
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+{
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+  handle_interrupts(_timer4, &TCNT4, &OCR4A);
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+}
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+#endif
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+
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+#if defined(_useTimer5)
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+SIGNAL (TIMER5_COMPA_vect)
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+{
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+  handle_interrupts(_timer5, &TCNT5, &OCR5A);
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+}
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+#endif
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+
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+#elif defined WIRING
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+// Interrupt handlers for Wiring
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+#if defined(_useTimer1)
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+void Timer1Service()
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+{
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+  handle_interrupts(_timer1, &TCNT1, &OCR1A);
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+}
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+#endif
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+#if defined(_useTimer3)
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+void Timer3Service()
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+{
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+  handle_interrupts(_timer3, &TCNT3, &OCR3A);
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+}
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+#endif
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+#endif
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+
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+
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+static void initISR(timer16_Sequence_t timer)
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+{
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+#if defined (_useTimer1)
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+  if(timer == _timer1) {
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+    TCCR1A = 0;             // normal counting mode
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+    TCCR1B = _BV(CS11);     // set prescaler of 8
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+    TCNT1 = 0;              // clear the timer count
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+#if defined(__AVR_ATmega8__)|| defined(__AVR_ATmega128__)
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+    TIFR |= _BV(OCF1A);      // clear any pending interrupts;
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+    TIMSK |=  _BV(OCIE1A) ;  // enable the output compare interrupt
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+#else
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+    // here if not ATmega8 or ATmega128
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+    TIFR1 |= _BV(OCF1A);     // clear any pending interrupts;
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+    TIMSK1 |=  _BV(OCIE1A) ; // enable the output compare interrupt
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+#endif
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+#if defined(WIRING)
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+    timerAttach(TIMER1OUTCOMPAREA_INT, Timer1Service);
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+#endif
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+  }
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+#endif
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+
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+#if defined (_useTimer3)
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+  if(timer == _timer3) {
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+    TCCR3A = 0;             // normal counting mode
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+    TCCR3B = _BV(CS31);     // set prescaler of 8
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+    TCNT3 = 0;              // clear the timer count
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+#if defined(__AVR_ATmega128__)
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+    TIFR |= _BV(OCF3A);     // clear any pending interrupts;
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+	ETIMSK |= _BV(OCIE3A);  // enable the output compare interrupt
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+#else
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+    TIFR3 = _BV(OCF3A);     // clear any pending interrupts;
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+    TIMSK3 =  _BV(OCIE3A) ; // enable the output compare interrupt
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+#endif
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+#if defined(WIRING)
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+    timerAttach(TIMER3OUTCOMPAREA_INT, Timer3Service);  // for Wiring platform only
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+#endif
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+  }
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+#endif
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+
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+#if defined (_useTimer4)
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+  if(timer == _timer4) {
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+    TCCR4A = 0;             // normal counting mode
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+    TCCR4B = _BV(CS41);     // set prescaler of 8
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+    TCNT4 = 0;              // clear the timer count
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+    TIFR4 = _BV(OCF4A);     // clear any pending interrupts;
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+    TIMSK4 =  _BV(OCIE4A) ; // enable the output compare interrupt
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+  }
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+#endif
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+
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+#if defined (_useTimer5)
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+  if(timer == _timer5) {
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+    TCCR5A = 0;             // normal counting mode
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+    TCCR5B = _BV(CS51);     // set prescaler of 8
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+    TCNT5 = 0;              // clear the timer count
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+    TIFR5 = _BV(OCF5A);     // clear any pending interrupts;
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+    TIMSK5 =  _BV(OCIE5A) ; // enable the output compare interrupt
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+  }
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+#endif
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+}
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+
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+static void finISR(timer16_Sequence_t timer)
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+{
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+    //disable use of the given timer
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+#if defined WIRING   // Wiring
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+  if(timer == _timer1) {
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+    #if defined(__AVR_ATmega1281__)||defined(__AVR_ATmega2561__)
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+    TIMSK1 &=  ~_BV(OCIE1A) ;  // disable timer 1 output compare interrupt
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+    #else
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+    TIMSK &=  ~_BV(OCIE1A) ;  // disable timer 1 output compare interrupt
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+    #endif
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+    timerDetach(TIMER1OUTCOMPAREA_INT);
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+  }
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+  else if(timer == _timer3) {
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+    #if defined(__AVR_ATmega1281__)||defined(__AVR_ATmega2561__)
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+    TIMSK3 &= ~_BV(OCIE3A);    // disable the timer3 output compare A interrupt
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+    #else
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+    ETIMSK &= ~_BV(OCIE3A);    // disable the timer3 output compare A interrupt
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+    #endif
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+    timerDetach(TIMER3OUTCOMPAREA_INT);
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+  }
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+#else
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+    //For arduino - in future: call here to a currently undefined function to reset the timer
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+#endif
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+}
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+
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+static boolean isTimerActive(timer16_Sequence_t timer)
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+{
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+  // returns true if any servo is active on this timer
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+  for(uint8_t channel=0; channel < SERVOS_PER_TIMER; channel++) {
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+    if(SERVO(timer,channel).Pin.isActive == true)
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+      return true;
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+  }
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+  return false;
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+}
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+
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+
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+/****************** end of static functions ******************************/
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+
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+Servo::Servo()
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+{
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+  if( ServoCount < MAX_SERVOS) {
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+    this->servoIndex = ServoCount++;                    // assign a servo index to this instance
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+	servos[this->servoIndex].ticks = usToTicks(DEFAULT_PULSE_WIDTH);   // store default values  - 12 Aug 2009
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+  }
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+  else
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+    this->servoIndex = INVALID_SERVO ;  // too many servos
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+}
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+
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+uint8_t Servo::attach(int pin)
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+{
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+  return this->attach(pin, MIN_PULSE_WIDTH, MAX_PULSE_WIDTH);
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+}
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+
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+uint8_t Servo::attach(int pin, int min, int max)
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+{
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+  if(this->servoIndex < MAX_SERVOS ) {
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+    pinMode( pin, OUTPUT) ;                                   // set servo pin to output
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+    servos[this->servoIndex].Pin.nbr = pin;
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+    // todo min/max check: abs(min - MIN_PULSE_WIDTH) /4 < 128
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+    this->min  = (MIN_PULSE_WIDTH - min)/4; //resolution of min/max is 4 uS
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+    this->max  = (MAX_PULSE_WIDTH - max)/4;
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+    // initialize the timer if it has not already been initialized
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+    timer16_Sequence_t timer = SERVO_INDEX_TO_TIMER(servoIndex);
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+    if(isTimerActive(timer) == false)
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+      initISR(timer);
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+    servos[this->servoIndex].Pin.isActive = true;  // this must be set after the check for isTimerActive
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+  }
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+  return this->servoIndex ;
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+}
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+
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+void Servo::detach()
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+{
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+  servos[this->servoIndex].Pin.isActive = false;
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+  timer16_Sequence_t timer = SERVO_INDEX_TO_TIMER(servoIndex);
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+  if(isTimerActive(timer) == false) {
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+    finISR(timer);
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+  }
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+}
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+
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+void Servo::write(int value)
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+{
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+  if(value < MIN_PULSE_WIDTH)
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+  {  // treat values less than 544 as angles in degrees (valid values in microseconds are handled as microseconds)
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+    if(value < 0) value = 0;
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+    if(value > 180) value = 180;
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+    value = map(value, 0, 180, SERVO_MIN(),  SERVO_MAX());
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+  }
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+  this->writeMicroseconds(value);
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+}
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+
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+void Servo::writeMicroseconds(int value)
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+{
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+  // calculate and store the values for the given channel
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+  byte channel = this->servoIndex;
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+  if( (channel < MAX_SERVOS) )   // ensure channel is valid
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+  {
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+    if( value < SERVO_MIN() )          // ensure pulse width is valid
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+      value = SERVO_MIN();
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+    else if( value > SERVO_MAX() )
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+      value = SERVO_MAX();
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+
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+  	value = value - TRIM_DURATION;
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+    value = usToTicks(value);  // convert to ticks after compensating for interrupt overhead - 12 Aug 2009
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+
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+    uint8_t oldSREG = SREG;
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+    cli();
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+    servos[channel].ticks = value;
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+    SREG = oldSREG;
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+  }
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+}
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+
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+int Servo::read() // return the value as degrees
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+{
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+  return  map( this->readMicroseconds()+1, SERVO_MIN(), SERVO_MAX(), 0, 180);
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+}
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+
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+int Servo::readMicroseconds()
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+{
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+  unsigned int pulsewidth;
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+  if( this->servoIndex != INVALID_SERVO )
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+    pulsewidth = ticksToUs(servos[this->servoIndex].ticks)  + TRIM_DURATION ;   // 12 aug 2009
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+  else
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+    pulsewidth  = 0;
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+
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+  return pulsewidth;
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+}
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+
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+bool Servo::attached()
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+{
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+  return servos[this->servoIndex].Pin.isActive ;
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+}

+ 126
- 0
Marlin/Servo.h View File

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+/*
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+  Servo.h - Interrupt driven Servo library for Arduino using 16 bit timers- Version 2
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+  Copyright (c) 2009 Michael Margolis.  All right reserved.
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+
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+  This library is free software; you can redistribute it and/or
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+  modify it under the terms of the GNU Lesser General Public
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+  License as published by the Free Software Foundation; either
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+  version 2.1 of the License, or (at your option) any later version.
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+
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+  This library is distributed in the hope that it will be useful,
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+  but WITHOUT ANY WARRANTY; without even the implied warranty of
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+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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+  Lesser General Public License for more details.
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+
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+  You should have received a copy of the GNU Lesser General Public
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+  License along with this library; if not, write to the Free Software
17
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
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+*/
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+
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+/*
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+
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+  A servo is activated by creating an instance of the Servo class passing the desired pin to the attach() method.
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+  The servos are pulsed in the background using the value most recently written using the write() method
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+
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+  Note that analogWrite of PWM on pins associated with the timer are disabled when the first servo is attached.
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+  Timers are seized as needed in groups of 12 servos - 24 servos use two timers, 48 servos will use four.
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+  The sequence used to sieze timers is defined in timers.h
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+
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+  The methods are:
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+
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+   Servo - Class for manipulating servo motors connected to Arduino pins.
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+
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+   attach(pin )  - Attaches a servo motor to an i/o pin.
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+   attach(pin, min, max  ) - Attaches to a pin setting min and max values in microseconds
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+   default min is 544, max is 2400
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+
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+   write()     - Sets the servo angle in degrees.  (invalid angle that is valid as pulse in microseconds is treated as microseconds)
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+   writeMicroseconds() - Sets the servo pulse width in microseconds
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+   read()      - Gets the last written servo pulse width as an angle between 0 and 180.
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+   readMicroseconds()   - Gets the last written servo pulse width in microseconds. (was read_us() in first release)
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+   attached()  - Returns true if there is a servo attached.
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+   detach()    - Stops an attached servos from pulsing its i/o pin.
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+ */
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+
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+#ifndef Servo_h
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+#define Servo_h
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+
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+#include <inttypes.h>
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+
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+/*
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+ * Defines for 16 bit timers used with  Servo library
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+ *
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+ * If _useTimerX is defined then TimerX is a 16 bit timer on the curent board
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+ * timer16_Sequence_t enumerates the sequence that the timers should be allocated
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+ * _Nbr_16timers indicates how many 16 bit timers are available.
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+ *
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+ */
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+
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+// Say which 16 bit timers can be used and in what order
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+#if defined(__AVR_ATmega1280__) || defined(__AVR_ATmega2560__)
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+#define _useTimer5
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+#define _useTimer1
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+#define _useTimer3
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+#define _useTimer4
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+typedef enum { _timer5, _timer1, _timer3, _timer4, _Nbr_16timers } timer16_Sequence_t ;
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+
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+#elif defined(__AVR_ATmega32U4__)
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+#define _useTimer1
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+typedef enum { _timer1, _Nbr_16timers } timer16_Sequence_t ;
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+
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+#elif defined(__AVR_AT90USB646__) || defined(__AVR_AT90USB1286__)
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+#define _useTimer3
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+#define _useTimer1
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+typedef enum { _timer3, _timer1, _Nbr_16timers } timer16_Sequence_t ;
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+
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+#elif defined(__AVR_ATmega128__) ||defined(__AVR_ATmega1281__)||defined(__AVR_ATmega2561__)
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+#define _useTimer3
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+#define _useTimer1
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+typedef enum { _timer3, _timer1, _Nbr_16timers } timer16_Sequence_t ;
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+
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+#else  // everything else
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+#define _useTimer1
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+typedef enum { _timer1, _Nbr_16timers } timer16_Sequence_t ;
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+#endif
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+
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+#define Servo_VERSION           2      // software version of this library
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+
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+#define MIN_PULSE_WIDTH       544     // the shortest pulse sent to a servo
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+#define MAX_PULSE_WIDTH      2400     // the longest pulse sent to a servo
90
+#define DEFAULT_PULSE_WIDTH  1500     // default pulse width when servo is attached
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+#define REFRESH_INTERVAL    20000     // minumim time to refresh servos in microseconds
92
+
93
+#define SERVOS_PER_TIMER       12     // the maximum number of servos controlled by one timer
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+#define MAX_SERVOS   (_Nbr_16timers  * SERVOS_PER_TIMER)
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+
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+#define INVALID_SERVO         255     // flag indicating an invalid servo index
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+
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+typedef struct  {
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+  uint8_t nbr        :6 ;             // a pin number from 0 to 63
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+  uint8_t isActive   :1 ;             // true if this channel is enabled, pin not pulsed if false
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+} ServoPin_t   ;
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+
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+typedef struct {
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+  ServoPin_t Pin;
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+  unsigned int ticks;
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+} servo_t;
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+
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+class Servo
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+{
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+public:
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+  Servo();
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+  uint8_t attach(int pin);           // attach the given pin to the next free channel, sets pinMode, returns channel number or 0 if failure
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+  uint8_t attach(int pin, int min, int max); // as above but also sets min and max values for writes.
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+  void detach();
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+  void write(int value);             // if value is < 200 its treated as an angle, otherwise as pulse width in microseconds
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+  void writeMicroseconds(int value); // Write pulse width in microseconds
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+  int read();                        // returns current pulse width as an angle between 0 and 180 degrees
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+  int readMicroseconds();            // returns current pulse width in microseconds for this servo (was read_us() in first release)
119
+  bool attached();                   // return true if this servo is attached, otherwise false
120
+private:
121
+   uint8_t servoIndex;               // index into the channel data for this servo
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+   int8_t min;                       // minimum is this value times 4 added to MIN_PULSE_WIDTH
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+   int8_t max;                       // maximum is this value times 4 added to MAX_PULSE_WIDTH
124
+};
125
+
126
+#endif

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