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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><meta http-equiv="Content-Type" content="text/html;charset=iso-8859-1"><title>Procyon AVRlib: timer.c Source File</title><link href="dox.css" rel="stylesheet" type="text/css"></head><body><!-- Generated by Doxygen 1.4.2 --><div class="qindex"><a class="qindex" href="main.html">Main Page</a> | <a class="qindex" href="modules.html">Modules</a> | <a class="qindex" href="annotated.html">Data Structures</a> | <a class="qindex" href="dirs.html">Directories</a> | <a class="qindex" href="files.html">File List</a> | <a class="qindex" href="functions.html">Data Fields</a> | <a class="qindex" href="globals.html">Globals</a> | <a class="qindex" href="pages.html">Related Pages</a></div><h1>timer.c</h1><a href="timer_8c.html">Go to the documentation of this file.</a><div class="fragment"><pre class="fragment">00001 <span class="comment">/*! \file timer.c \brief System Timer function library. */</span>00002 <span class="comment">//*****************************************************************************</span>00003 <span class="comment">//</span>00004 <span class="comment">// File Name : 'timer.c'</span>00005 <span class="comment">// Title : System Timer function library</span>00006 <span class="comment">// Author : Pascal Stang - Copyright (C) 2000-2002</span>00007 <span class="comment">// Created : 11/22/2000</span>00008 <span class="comment">// Revised : 07/09/2003</span>00009 <span class="comment">// Version : 1.1</span>00010 <span class="comment">// Target MCU : Atmel AVR Series</span>00011 <span class="comment">// Editor Tabs : 4</span>00012 <span class="comment">//</span>00013 <span class="comment">// This code is distributed under the GNU Public License</span>00014 <span class="comment">// which can be found at http://www.gnu.org/licenses/gpl.txt</span>00015 <span class="comment">//</span>00016 <span class="comment">//*****************************************************************************</span>00017 00018 <span class="preprocessor">#include <avr/io.h></span>00019 <span class="preprocessor">#include <avr/interrupt.h></span>00020 <span class="preprocessor">#include <avr/pgmspace.h></span>00021 <span class="preprocessor">#include <avr/sleep.h></span>00022 00023 <span class="preprocessor">#include "<a class="code" href="global_8h.html">global.h</a>"</span>00024 <span class="preprocessor">#include "<a class="code" href="timer_8h.html">timer.h</a>"</span>00025 00026 <span class="preprocessor">#include "<a class="code" href="rprintf_8h.html">rprintf.h</a>"</span>00027 00028 <span class="comment">// Program ROM constants</span>00029 <span class="comment">// the prescale division values stored in order of timer control register index</span>00030 <span class="comment">// STOP, CLK, CLK/8, CLK/64, CLK/256, CLK/1024</span>00031 <span class="keywordtype">unsigned</span> <span class="keywordtype">short</span> __attribute__ ((progmem)) TimerPrescaleFactor[] = {0,1,8,64,256,1024};00032 <span class="comment">// the prescale division values stored in order of timer control register index</span>00033 <span class="comment">// STOP, CLK, CLK/8, CLK/32, CLK/64, CLK/128, CLK/256, CLK/1024</span>00034 <span class="keywordtype">unsigned</span> <span class="keywordtype">short</span> __attribute__ ((progmem)) TimerRTCPrescaleFactor[] = {0,1,8,32,64,128,256,1024};00035 00036 <span class="comment">// Global variables</span>00037 <span class="comment">// time registers</span>00038 <span class="keyword">volatile</span> <span class="keywordtype">unsigned</span> <span class="keywordtype">long</span> TimerPauseReg;00039 <span class="keyword">volatile</span> <span class="keywordtype">unsigned</span> <span class="keywordtype">long</span> Timer0Reg0;00040 <span class="keyword">volatile</span> <span class="keywordtype">unsigned</span> <span class="keywordtype">long</span> Timer2Reg0;00041 00042 <span class="keyword">typedef</span> void (*voidFuncPtr)(void);00043 <span class="keyword">volatile</span> <span class="keyword">static</span> voidFuncPtr TimerIntFunc[TIMER_NUM_INTERRUPTS];00044 00045 <span class="comment">// delay for a minimum of <us> microseconds </span>00046 <span class="comment">// the time resolution is dependent on the time the loop takes </span>00047 <span class="comment">// e.g. with 4Mhz and 5 cycles per loop, the resolution is 1.25 us </span>00048 <span class="keywordtype">void</span> delay_us(<span class="keywordtype">unsigned</span> <span class="keywordtype">short</span> time_us) 00049 {00050 <span class="keywordtype">unsigned</span> <span class="keywordtype">short</span> delay_loops;00051 <span class="keyword">register</span> <span class="keywordtype">unsigned</span> <span class="keywordtype">short</span> i;00052 00053 delay_loops = (time_us+3)/5*CYCLES_PER_US; <span class="comment">// +3 for rounding up (dirty) </span>00054 00055 <span class="comment">// one loop takes 5 cpu cycles </span>00056 <span class="keywordflow">for</span> (i=0; i < delay_loops; i++) {};00057 }00058 <span class="comment">/*</span>00059 <span class="comment">void delay_ms(unsigned char time_ms)</span>00060 <span class="comment">{</span>00061 <span class="comment"> unsigned short delay_count = F_CPU / 4000;</span>00062 <span class="comment"></span>00063 <span class="comment"> unsigned short cnt;</span>00064 <span class="comment"> asm volatile ("\n"</span>00065 <span class="comment"> "L_dl1%=:\n\t"</span>00066 <span class="comment"> "mov %A0, %A2\n\t"</span>00067 <span class="comment"> "mov %B0, %B2\n"</span>00068 <span class="comment"> "L_dl2%=:\n\t"</span>00069 <span class="comment"> "sbiw %A0, 1\n\t"</span>00070 <span class="comment"> "brne L_dl2%=\n\t"</span>00071 <span class="comment"> "dec %1\n\t" "brne L_dl1%=\n\t":"=&w" (cnt)</span>00072 <span class="comment"> :"r"(time_ms), "r"((unsigned short) (delay_count))</span>00073 <span class="comment"> );</span>00074 <span class="comment">}</span>00075 <span class="comment">*/</span><a name="l00076"></a><a class="code" href="group__timerx8.html#ga1">00076</a> <span class="keywordtype">void</span> <a class="code" href="group__timer.html#ga1">timerInit</a>(<span class="keywordtype">void</span>)00077 {00078 u08 intNum;00079 <span class="comment">// detach all user functions from interrupts</span>00080 <span class="keywordflow">for</span>(intNum=0; intNum<TIMER_NUM_INTERRUPTS; intNum++)00081 <a class="code" href="group__timer.html#ga9">timerDetach</a>(intNum);00082 00083 <span class="comment">// initialize all timers</span>00084 <a class="code" href="group__timer.html#ga2">timer0Init</a>();00085 <a class="code" href="group__timer.html#ga3">timer1Init</a>();00086 <span class="preprocessor"> #ifdef TCNT2 // support timer2 only if it exists</span>00087 <span class="preprocessor"></span> timer2Init();00088 <span class="preprocessor"> #endif</span>00089 <span class="preprocessor"></span> <span class="comment">// enable interrupts</span>00090 sei();00091 }00092 <a name="l00093"></a><a class="code" href="group__timerx8.html#ga2">00093</a> <span class="keywordtype">void</span> <a class="code" href="group__timer.html#ga2">timer0Init</a>()00094 {00095 <span class="comment">// initialize timer 0</span>00096 <a class="code" href="group__timer.html#ga4">timer0SetPrescaler</a>( <a class="code" href="group__timer.html#ga33">TIMER0PRESCALE</a> ); <span class="comment">// set prescaler</span>00097 outb(TCNT0, 0); <span class="comment">// reset TCNT0</span>00098 sbi(TIMSK, TOIE0); <span class="comment">// enable TCNT0 overflow interrupt</span>00099 00100 <a class="code" href="group__timer.html#ga11">timer0ClearOverflowCount</a>(); <span class="comment">// initialize time registers</span>00101 }00102 <a name="l00103"></a><a class="code" href="group__timerx8.html#ga3">00103</a> <span class="keywordtype">void</span> <a class="code" href="group__timer.html#ga3">timer1Init</a>(<span class="keywordtype">void</span>)00104 {00105 <span class="comment">// initialize timer 1</span>00106 <a class="code" href="group__timer.html#ga6">timer1SetPrescaler</a>( <a class="code" href="group__timer.html#ga34">TIMER1PRESCALE</a> ); <span class="comment">// set prescaler</span>00107 outb(TCNT1H, 0); <span class="comment">// reset TCNT1</span>00108 outb(TCNT1L, 0);00109 sbi(TIMSK, TOIE1); <span class="comment">// enable TCNT1 overflow</span>00110 }00111 00112 <span class="preprocessor">#ifdef TCNT2 // support timer2 only if it exists</span>00113 <span class="preprocessor"></span><span class="keywordtype">void</span> timer2Init(<span class="keywordtype">void</span>)00114 {00115 <span class="comment">// initialize timer 2</span>00116 <a class="code" href="group__timer128.html#ga8">timer2SetPrescaler</a>( <a class="code" href="group__timer.html#ga35">TIMER2PRESCALE</a> ); <span class="comment">// set prescaler</span>00117 outb(TCNT2, 0); <span class="comment">// reset TCNT2</span>00118 sbi(TIMSK, TOIE2); <span class="comment">// enable TCNT2 overflow</span>00119 00120 timer2ClearOverflowCount(); <span class="comment">// initialize time registers</span>00121 }00122 <span class="preprocessor">#endif</span>00123 <span class="preprocessor"></span><a name="l00124"></a><a class="code" href="group__timerx8.html#ga4">00124</a> <span class="keywordtype">void</span> <a class="code" href="group__timer.html#ga4">timer0SetPrescaler</a>(u08 prescale)00125 {00126 <span class="comment">// set prescaler on timer 0</span>00127 outb(TCCR0, (inb(TCCR0) & ~<a class="code" href="group__timer.html#ga23">TIMER_PRESCALE_MASK</a>) | prescale);00128 }00129 <a name="l00130"></a><a class="code" href="group__timerx8.html#ga6">00130</a> <span class="keywordtype">void</span> <a class="code" href="group__timer.html#ga6">timer1SetPrescaler</a>(u08 prescale)00131 {00132 <span class="comment">// set prescaler on timer 1</span>00133 outb(TCCR1B, (inb(TCCR1B) & ~<a class="code" href="group__timer.html#ga23">TIMER_PRESCALE_MASK</a>) | prescale);00134 }00135 00136 <span class="preprocessor">#ifdef TCNT2 // support timer2 only if it exists</span>00137 <span class="preprocessor"></span><span class="keywordtype">void</span> <a class="code" href="group__timer128.html#ga8">timer2SetPrescaler</a>(u08 prescale)00138 {00139 <span class="comment">// set prescaler on timer 2</span>00140 outb(TCCR2, (inb(TCCR2) & ~<a class="code" href="group__timer.html#ga23">TIMER_PRESCALE_MASK</a>) | prescale);00141 }00142 <span class="preprocessor">#endif</span>00143 <span class="preprocessor"></span><a name="l00144"></a><a class="code" href="group__timerx8.html#ga5">00144</a> u16 <a class="code" href="group__timer.html#ga5">timer0GetPrescaler</a>(<span class="keywordtype">void</span>)00145 {00146 <span class="comment">// get the current prescaler setting</span>00147 <span class="keywordflow">return</span> (pgm_read_word(TimerPrescaleFactor+(inb(TCCR0) & <a class="code" href="group__timer.html#ga23">TIMER_PRESCALE_MASK</a>)));00148 }00149 <a name="l00150"></a><a class="code" href="group__timerx8.html#ga7">00150</a> u16 <a class="code" href="group__timer.html#ga7">timer1GetPrescaler</a>(<span class="keywordtype">void</span>)00151 {00152 <span class="comment">// get the current prescaler setting</span>00153 <span class="keywordflow">return</span> (pgm_read_word(TimerPrescaleFactor+(inb(TCCR1B) & <a class="code" href="group__timer.html#ga23">TIMER_PRESCALE_MASK</a>)));00154 }⌨️ 快捷键说明
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