?? 2440beep.c
字號:
#include "2440addr.h"
#include "2440lib.h"
#include "def.h"
/****************************************************************************
【功能說明】蜂鳴器PWM測試
****************************************************************************/
void Buzzer_Freq_Set( U32 freq )
{
//set GPB1 as TOUT1, pwm output
rGPBCON = rGPBCON &~(3<<2)|(1<<3);
rTCFG0 = rTCFG0 &~(0xff)|(15);
rTCFG1 = rTCFG1 &~(0xf<<4)|(1<<5);
rTCNTB1 = (PCLK>>7)/freq;
rTCMPB1 = rTCNTB1>>1; // 50%
//disable deadzone, auto-reload, inv-off, update TCNTB1&TCMPB1, start timer 1
rTCON = rTCON &~(0xf<<8)|(0xb<<8);
rTCON &= ~(1<<9); //clear manual update bit
}
void Buzzer_Stop( void )
{
rGPBCON &= ~12; //set GPB1 as output
rGPBCON |= 4;
rGPBDAT &= ~1;
}
void Buzzer_PWM_Run( void )
{
U16 freq = 2000 ;
Buzzer_Freq_Set( freq ) ;
}
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