peter@520: /*
peter@520: This file is part of CanFestival, a library implementing CanOpen Stack.
peter@520: 
peter@520: Copyright (C): Edouard TISSERANT and Francis DUPIN
peter@520: AT91 Port: Peter CHRISTEN
peter@520: 
peter@520: See COPYING file for copyrights details.
peter@520: 
peter@520: This library is free software; you can redistribute it and/or
peter@520: modify it under the terms of the GNU Lesser General Public
peter@520: License as published by the Free Software Foundation; either
peter@520: version 2.1 of the License, or (at your option) any later version.
peter@520: 
peter@520: This library is distributed in the hope that it will be useful,
peter@520: but WITHOUT ANY WARRANTY; without even the implied warranty of
peter@520: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
peter@520: Lesser General Public License for more details.
peter@520: 
peter@520: You should have received a copy of the GNU Lesser General Public
peter@520: License along with this library; if not, write to the Free Software
peter@520: Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
peter@520: */
peter@520: 
peter@520: // Includes for the Canfestival driver
peter@520: #include "canfestival.h"
Edouard@801: #include "timers.h"
peter@520: 
peter@520: // Define the timer registers
peter@520: #define AT91C_BASE_TC	AT91C_BASE_TC2
peter@520: #define AT91C_ID_TC	AT91C_ID_TC2
peter@520: #define TimerAlarm      AT91C_BASE_TC2->TC_RC
peter@520: #define TimerCounter    AT91C_BASE_TC2->TC_CV
peter@520: 
peter@520: #define TIMER_INTERRUPT_LEVEL		1
peter@520: 
peter@520: void timer_can_irq_handler(void);
peter@520: 
peter@520: 
peter@520: /************************** Modul variables **********************************/
peter@520: // Store the last timer value to calculate the elapsed time
peter@520: static TIMEVAL last_time_set = TIMEVAL_MAX;
peter@520: 
peter@520: void initTimer(void)
peter@520: /******************************************************************************
peter@520: Initializes the timer, turn on the interrupt and put the interrupt time to zero
peter@520: INPUT	void
peter@520: OUTPUT	void
peter@520: ******************************************************************************/
peter@520: {
peter@520:   unsigned int dummy;
peter@520: 
peter@520:   // First, enable the clock of the TIMER
peter@520:   AT91F_PMC_EnablePeriphClock (AT91C_BASE_PMC, 1 << AT91C_ID_TC);
peter@520:   // Disable the clock and the interrupts
peter@520:   AT91C_BASE_TC->TC_CCR = AT91C_TC_CLKDIS ;
peter@520:   AT91C_BASE_TC->TC_IDR = 0xFFFFFFFF ;
peter@520:   // Clear status bit
peter@520:   dummy = AT91C_BASE_TC->TC_SR;
peter@520:   // Suppress warning variable "dummy" was set but never used
peter@520:   dummy = dummy;
peter@520: 
peter@520:   // Set the Mode of the Timer Counter (MCK / 128)
peter@520:   AT91C_BASE_TC->TC_CMR = AT91C_TC_CLKS_TIMER_DIV4_CLOCK;
peter@520: 
peter@520:   // Enable the clock
peter@520:   AT91C_BASE_TC->TC_CCR = AT91C_TC_CLKEN ;
peter@520: 
peter@520:   // Open Timer interrupt
peter@520:   AT91F_AIC_ConfigureIt (AT91C_BASE_AIC, AT91C_ID_TC, TIMER_INTERRUPT_LEVEL,
peter@520: 			 AT91C_AIC_SRCTYPE_INT_POSITIVE_EDGE, timer_can_irq_handler);
peter@520: 
peter@520:   AT91C_BASE_TC->TC_IER = AT91C_TC_CPCS;  //  IRQ enable CPC
peter@520:   AT91F_AIC_EnableIt (AT91C_BASE_AIC, AT91C_ID_TC2);
peter@520: 
peter@520:   // Start Timer
peter@520:   AT91C_BASE_TC->TC_CCR = AT91C_TC_SWTRG ;
peter@520: }
peter@520: 
peter@520: void setTimer(TIMEVAL value)
peter@520: /******************************************************************************
peter@520: Set the timer for the next alarm.
peter@520: INPUT	value TIMEVAL (unsigned long)
peter@520: OUTPUT	void
peter@520: ******************************************************************************/
peter@520: {
peter@520:   TimerAlarm += value;	// Add the desired time to timer interrupt time
peter@520: }
peter@520: 
peter@520: TIMEVAL getElapsedTime(void)
peter@520: /******************************************************************************
peter@520: Return the elapsed time to tell the stack how much time is spent since last call.
peter@520: INPUT	void
peter@520: OUTPUT	value TIMEVAL (unsigned long) the elapsed time
peter@520: ******************************************************************************/
peter@520: {
peter@520:   unsigned int timer = TimerCounter;	// Copy the value of the running timer
peter@520:   // Calculate the time difference
peter@520:   return timer > last_time_set ? timer - last_time_set : last_time_set - timer;
peter@520: }
peter@520: 
peter@520: 
peter@520: //*----------------------------------------------------------------------------
peter@520: //* Function Name       : timer_can_irq_handler
peter@520: //* Object              : C handler interrupt function by the interrupts
peter@520: //*                       assembling routine
peter@520: //* Output Parameters   : calls TimeDispatch
peter@520: //*----------------------------------------------------------------------------
peter@520: void timer_can_irq_handler(void)
peter@520: {
peter@520:   AT91PS_TC TC_pt = AT91C_BASE_TC;
peter@520:   unsigned int dummy;
peter@520:   // AcknowAT91B_LEDge interrupt status
peter@520:   dummy = TC_pt->TC_SR;
peter@520:   // Suppress warning variable "dummy" was set but never used
peter@520:   dummy = dummy;
peter@520:   last_time_set = TimerCounter;
peter@520:   TimeDispatch();	// Call the time handler of the stack to adapt the elapsed time
peter@520: }
peter@520: