Files
bacnet_stack/ports/xplained/mstimer-init.c
T
Steve Karg 0001f85f29 Bugfix/network port object link speeds (#488)
* fix ports/xplained build under Linux

* fix network port object link-speeds property

---------

Co-authored-by: Steve Karg <skarg@users.sourceforge.net>
2023-09-08 17:41:56 -05:00

110 lines
3.6 KiB
C

/*
* @file
*
* @brief 1ms timer configuration
*
* Copyright (C) 2009 Steve Karg <skarg@users.sourceforge.net>
*
* Created: 10/24/2013 8:58:56 PM
* Author: Steve
*
* @page License
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <stdint.h>
#include <stdbool.h>
#include <stddef.h>
#include "tc.h"
#include "bacnet/basic/sys/mstimer.h"
/* define which timer for the counter we are using */
#define MS_TIMER_COUNTER TCE0
/* define which timer for the callback we are using */
#define MS_TIMER_CALLBACK TCE1
/* counter for the base timer */
static volatile uint32_t Millisecond_Counter;
/**
* Handles an interrupt from a hardware counter timer, every millisecond
*/
static void mstimer_counter_handler(void)
{
Millisecond_Counter++;
}
/**
* Handles an interrupt from an overflow hardware timer, every millisecond
*/
static void mstimer_overflow_handler(void)
{
/* callback might go too long; prevent re-entrency by disable IRQ source */
tc_set_overflow_interrupt_level(&MS_TIMER_CALLBACK, TC_INT_LVL_OFF);
mstimer_callback_handler();
tc_set_overflow_interrupt_level(&MS_TIMER_CALLBACK, TC_INT_LVL_LO);
}
/**
* Returns the continuous milliseconds count, which rolls over
*
* @return the current milliseconds count
*/
unsigned long mstimer_now(void)
{
uint32_t timer_value; /* return value */
tc_set_overflow_interrupt_level(&MS_TIMER_COUNTER, TC_INT_LVL_OFF);
timer_value = Millisecond_Counter;
tc_set_overflow_interrupt_level(&MS_TIMER_COUNTER, TC_INT_LVL_LO);
return timer_value;
}
/**
* Timer setup for 1 millisecond timer
*/
void mstimer_init(void)
{
unsigned long period;
tc_enable(&MS_TIMER_COUNTER);
tc_set_overflow_interrupt_callback(&MS_TIMER_COUNTER,
mstimer_counter_handler);
tc_set_wgm(&MS_TIMER_COUNTER, TC_WG_NORMAL);
tc_write_count(&MS_TIMER_COUNTER, 1);
period = sysclk_get_peripheral_bus_hz(&MS_TIMER_COUNTER);
period /= 1000;
tc_write_period(&MS_TIMER_COUNTER, period);
tc_set_overflow_interrupt_level(&MS_TIMER_COUNTER, TC_INT_LVL_LO);
tc_write_clock_source(&MS_TIMER_COUNTER, TC_CLKSEL_DIV1_gc);
tc_enable(&MS_TIMER_CALLBACK);
tc_set_overflow_interrupt_callback(&MS_TIMER_CALLBACK,
mstimer_overflow_handler);
tc_set_wgm(&MS_TIMER_CALLBACK, TC_WG_NORMAL);
tc_write_count(&MS_TIMER_CALLBACK, 1);
period = sysclk_get_peripheral_bus_hz(&MS_TIMER_CALLBACK);
period /= 1000;
tc_write_period(&MS_TIMER_CALLBACK, period);
tc_set_overflow_interrupt_level(&MS_TIMER_CALLBACK, TC_INT_LVL_LO);
tc_write_clock_source(&MS_TIMER_CALLBACK, TC_CLKSEL_DIV1_gc);
}