etisserant@375: /*
etisserant@375: This file is part of CanFestival, a library implementing CanOpen Stack.
etisserant@375: 
etisserant@375: Copyright (C): Edouard TISSERANT and Francis DUPIN
etisserant@375: AVR Port: Andreas GLAUSER and Peter CHRISTEN
etisserant@375: 
etisserant@375: See COPYING file for copyrights details.
etisserant@375: 
etisserant@375: This library is free software; you can redistribute it and/or
etisserant@375: modify it under the terms of the GNU Lesser General Public
etisserant@375: License as published by the Free Software Foundation; either
etisserant@375: version 2.1 of the License, or (at your option) any later version.
etisserant@375: 
etisserant@375: This library is distributed in the hope that it will be useful,
etisserant@375: but WITHOUT ANY WARRANTY; without even the implied warranty of
etisserant@375: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
etisserant@375: Lesser General Public License for more details.
etisserant@375: 
etisserant@375: You should have received a copy of the GNU Lesser General Public
etisserant@375: License along with this library; if not, write to the Free Software
etisserant@375: Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
etisserant@375: */
etisserant@375: 
etisserant@375: // AVR implementation of the  CANopen timer driver, uses Timer 3 (16 bit)
etisserant@375: 
etisserant@375: // Includes for the Canfestival driver
etisserant@375: #include "canfestival.h"
Edouard@801: #include "timers.h"
etisserant@375: 
etisserant@375: // Define the timer registers
etisserant@375: #define TimerAlarm        OCR3B
etisserant@375: #define TimerCounter      TCNT3
etisserant@375: 
etisserant@375: /************************** Modul variables **********************************/
etisserant@375: // Store the last timer value to calculate the elapsed time
etisserant@375: static TIMEVAL last_time_set = TIMEVAL_MAX;     
etisserant@375: 
etisserant@375: void initTimer(void)
etisserant@375: /******************************************************************************
etisserant@375: Initializes the timer, turn on the interrupt and put the interrupt time to zero
etisserant@375: INPUT	void
etisserant@375: OUTPUT	void
etisserant@375: ******************************************************************************/
etisserant@375: {
etisserant@375:   TimerAlarm = 0;		// Set it back to the zero
etisserant@375: 	// Set timer 3 for CANopen operation tick 8us max, time is 524ms
etisserant@375:   TCCR3B = 1 << CS31 | 1 << CS30;       // Timer 3 normal, mit CK/64
etisserant@375:   TIMSK3 = 1 << OCIE3B;                 // Enable the interrupt
etisserant@375: }
etisserant@375: 
etisserant@375: void setTimer(TIMEVAL value)
etisserant@375: /******************************************************************************
etisserant@375: Set the timer for the next alarm.
etisserant@375: INPUT	value TIMEVAL (unsigned long)
etisserant@375: OUTPUT	void
etisserant@375: ******************************************************************************/
etisserant@375: {
etisserant@375:   TimerAlarm += (int)value;	// Add the desired time to timer interrupt time
etisserant@375: }
etisserant@375: 
etisserant@375: TIMEVAL getElapsedTime(void)
etisserant@375: /******************************************************************************
etisserant@375: Return the elapsed time to tell the Stack how much time is spent since last call.
etisserant@375: INPUT	void
etisserant@375: OUTPUT	value TIMEVAL (unsigned long) the elapsed time
etisserant@375: ******************************************************************************/
etisserant@375: {
etisserant@375:   unsigned int timer = TimerCounter;            // Copy the value of the running timer
etisserant@375:   if (timer > last_time_set)                    // In case the timer value is higher than the last time.
etisserant@375:     return (timer - last_time_set);             // Calculate the time difference
etisserant@375:   else if (timer < last_time_set)
etisserant@375:     return (last_time_set - timer);             // Calculate the time difference
etisserant@375:   else
etisserant@375:     return TIMEVAL_MAX;
etisserant@375: }
etisserant@375: 
etisserant@375: #ifdef  __IAR_SYSTEMS_ICC__
etisserant@375: #pragma type_attribute = __interrupt
etisserant@375: #pragma vector=TIMER3_COMPB_vect
etisserant@375: void TIMER3_COMPB_interrupt(void)
etisserant@375: #else	// GCC
etisserant@375: ISR(TIMER3_COMPB_vect)
etisserant@375: #endif	// GCC
etisserant@375: /******************************************************************************
etisserant@375: Interruptserviceroutine Timer 3 Compare B for the CAN timer
etisserant@375: ******************************************************************************/
etisserant@375: {
etisserant@375:   last_time_set = TimerCounter;
etisserant@375:   TimeDispatch();                               // Call the time handler of the stack to adapt the elapsed time
etisserant@375: }
etisserant@375: 
etisserant@375: 
etisserant@375: