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/*
* Copyright 2003 by Texas Instruments Incorporated.
* All rights reserved. Property of Texas Instruments Incorporated.
* Restricted rights to use, duplicate or disclose this code are
* granted through contract.
*
*/
/* "@(#) DSP/BIOS 4.90.270 06-11-03 (barracuda-m10)" */
/******************************************************************************\
* Copyright (C) 2000 Texas Instruments Incorporated.
* All Rights Reserved
*------------------------------------------------------------------------------
* FILENAME...... timer.c
* DATE CREATED.. 01/11/2000
* LAST MODIFIED. 01/04/2001
\******************************************************************************/
#include <stdio.h>
#include <csl.h>
#include <csl_irq.h>
#include <csl_timer.h>
#include <csl_chiphal.h>
/* This is a simple timer example to set the timer with */
/* an interrupt period of 0x400 cycles. */
/* The example uses predefined CSL macros and symbolic */
/* constants to create the correct register settings */
/* needed to configure the timer. */
/* Reference start of interrupt vector table */
/* This symbol is defined in file, vectors.s55 */
extern void VECSTART(void);
#define TIMER_CTRL TIMER_TCR_RMK(\
TIMER_TCR_IDLEEN_DEFAULT, /* IDLEEN == 0 */ \
TIMER_TCR_FUNC_OF(0), /* FUNC == 0 */ \
TIMER_TCR_TLB_RESET, /* TLB == 1 */ \
TIMER_TCR_SOFT_BRKPTNOW, /* SOFT == 0 */ \
TIMER_TCR_FREE_WITHSOFT, /* FREE == 0 */ \
TIMER_TCR_PWID_OF(0), /* PWID == 0 */ \
TIMER_TCR_ARB_RESET, /* ARB == 1 */ \
TIMER_TCR_TSS_START, /* TSS == 0 */ \
TIMER_TCR_CP_PULSE, /* CP == 0 */ \
TIMER_TCR_POLAR_LOW, /* POLAR == 0 */ \
TIMER_TCR_DATOUT_0 /* DATOUT == 0 */ \
)
/* Create a TIMER configuration structure that can be passed */
/* to TIMER_config CSL function for initialization of Timer */
/* control registers. */
TIMER_Config timCfg0 = {
TIMER_CTRL, /* TCR0 */
0x3400u, /* PRD0 */
0x0000 /* PRSC */
};
Uint16 eventId0;
/* Create a TIMER_Handle object for use with TIMER_open */
TIMER_Handle mhTimer0;
volatile Uint16 timer0_cnt = 0;
/* Function/ISR prototypes */
interrupt void timer0Isr(void);
int old_intm;
Uint16 tim_val;
Uint16 xfchange = 0;
void main(void)
{
/* Initialize CSL library - This is REQUIRED !!! */
/*CLS库的初始化，这是必需的*/
CSL_init();
/* Set IVPH/IVPD to start of interrupt vector table */
/*修改寄存器IVPH，IVPD，重新定义中断向量表*/
IRQ_setVecs((Uint32)(&VECSTART));
/* Temporarily disable all maskable interrupts */
/*禁止所有可屏蔽的中断源*/
old_intm = IRQ_globalDisable();
/* Open Timer 0, set registers to power on defaults */
/*打开定时器0，设置其为上电的的默认值，并返回其句柄*/
mhTimer0 = TIMER_open(TIMER_DEV0, TIMER_OPEN_RESET);
/* Get Event Id associated with Timer 0, for use with */
/* CSL interrupt enable functions. */
/*获取定时器0的中断ID号*/
eventId0 = TIMER_getEventId(mhTimer0);
/* Clear any pending Timer interrupts */
/*清除定时器0的中断状态位*/
IRQ_clear(eventId0);
/* Place interrupt service routine address at */
/* associated vector location */
/*为定时器0设置中断服务程序*/
IRQ_plug(eventId0,&timer0Isr);
/* Write configuration structure values to Timer control regs */
/*设置定时器0的控制与周期寄存器*/
TIMER_config(mhTimer0, &timCfg0);
/* Enable Timer interrupt */
/*使能定时器的中断*/
IRQ_enable(eventId0);
/* Enable all maskable interrupts */
/*设置寄存器ST1的INTM位，使能所有的中断*/
IRQ_globalEnable();
/* Start Timer */
/*启动定时器0*/
TIMER_start(mhTimer0);
for(;;)
{
/* Wait for at least 10 timer periods */
/*等待10个定时周期*/
if(xfchange == 0)
{
/*点亮XF的LED*/
CHIP_FSET(ST1_55,XF,1);
}
else
{
/*关掉XF的LED*/
CHIP_FSET(ST1_55,XF,0);
}
}
/* Restore old value of INTM */
/*恢复INTM旧的值*/
IRQ_globalRestore(old_intm);
/* We are through with timer, so close it */
/*关掉定时器0*/
TIMER_close(mhTimer0);
}
/*定时器0的中断程序*/
interrupt void timer0Isr(void)
{
++timer0_cnt;
if(timer0_cnt == 500)
{
xfchange = 1;
}
if(timer0_cnt == 1000)
{
timer0_cnt = 0;
xfchange = 0;
}
}
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