plat_dep.c

MANTIS是由科罗拉多大学开发的传感器网络嵌入式操作系统。 这是mantis的0.9.5版本的源码。

//  This file is part of MANTIS OS, Operating System
//  See http://mantis.cs.colorado.edu/
//
//  Copyright (C) 2003,2004,2005 University of Colorado, Boulder
//
//  This program is free software; you can redistribute it and/or
//  modify it under the terms of the mos license (see file LICENSE)

#include "plat_dep.h"
#include "plat_clock.h"

// last_sleep_time declared in msched.c
extern uint16_t last_sleep_time;


handle_t mos_disable_ints(void)     
{
   handle_t sreg;

   sreg = SREG;
   cli();

   return sreg;
}


void kernel_timer_init(void)
{
   
   //set to CTC mode
   TSLICE_CNTRLA &= ~((1 << WGM11) | (1 << WGM10));
   TSLICE_CNTRLB &= ~((1 << WGM13));
   TSLICE_CNTRLB |= (1 << WGM12);

   //set the prescaler
   TSLICE_CNTRLB |= (1 << CS12) | (1 << CS10);
   TSLICE_CNTRLB &= ~(1 << CS11);

   //set ocr to 20 ms
   TSLICE_OCR = TIMESLICE_20_MS;

   //clear interrupt flag mask
   TIFR |= (1 << TSLICE_FLAG);
   TIMSK |= (1 << TSLICE_INT);
   
}


void sleep_timer_init(void)
{
   SLEEP_CNTRL &= ~(0 << SLEEP_INT);
   ASSR = 1 << AS0;

   //set prescaler and CTC mode
   SLEEP_CNTRL = (1 << CS02) | (1 << CS01) | (1 << CS00) | (1 << WGM01);
   SLEEP_CNTRL &= ~(1 << WGM00);

   SLEEP_CNT = 0;

   //set OCR to ??? ms
   SLEEP_OCR = 1;
   TIMSK &= ~(1 << SLEEP_INT);
   TIFR |= (1 << SLEEP_FLAG);

   last_sleep_time = 0;
}