NXP产品LPC23XX的开发板的源文件
源代码在线查看： pwm.c
/*****************************************************************************
* pwm.c: PWM module file for NXP LPC23xx/24xx Family Microprocessors
*
* Copyright(C) 2006, NXP Semiconductor
* All rights reserved.
*
* History
* 2006.07.20 ver 1.00 Prelimnary version, first Release
*
******************************************************************************/
#include "LPC23xx.h" /* LPC23xx/24xx definitions */
#include "type.h"
#include "irq.h"
#include "timer.h"
#include "pwm.h"
volatile DWORD match_counter0, match_counter1;
/******************************************************************************
** Function name: PWM0Handler
**
** Descriptions: PWM0 interrupt handler
** For now, it only deals with PWM1 match 0
**
** parameters: None
** Returned value: None
**
******************************************************************************/
void PWMHandler (void) __irq
{
DWORD regVal;
IENABLE; /* handles nested interrupt */
regVal = PWM0IR;
if ( regVal & MR0_INT )
{
match_counter0++;
}
PWM0IR |= regVal; /* clear interrupt flag on match 0 */
regVal = PWM1IR;
if ( regVal & MR0_INT )
{
match_counter1++;
}
PWM1IR |= regVal; /* clear interrupt flag on match 0 */
IDISABLE;
VICVectAddr = 0; /* Acknowledge Interrupt */
return;
}
/******************************************************************************
** Function name: PWM_Init
**
** Descriptions: PWM initialization, setup all GPIOs to PWM0~6,
** reset counter, all latches are enabled, interrupt
** on PWMMR0, install PWM interrupt to the VIC table.
**
** parameters: ChannelNum, Duty cycle
** Returned value: true or fase, if VIC table is full, return false
**
******************************************************************************/
DWORD PWM_Init( DWORD ChannelNum, DWORD cycle )
{
if ( ChannelNum == 0 )
{
match_counter0 = 0;
PINSEL7 = 0x00002AAA; /* set GPIOs for all PWM pins on PWM0 */
PWM0TCR = TCR_RESET; /* Counter Reset */
PWM0PR = 0x00; /* count frequency:Fpclk */
PWM0MCR = PWMMR0I | PWMMR0R; /* interrupt on PWMMR0, reset on PWMMR0, reset
TC if PWM0 matches */
PWM0MR0 = cycle; /* set PWM cycle */
PWM0MR1 = cycle * 5/6;
PWM0MR2 = cycle * 2/3;
PWM0MR3 = cycle * 1/2;
PWM0MR4 = cycle * 1/3;
PWM0MR5 = cycle * 1/6;
/* all PWM latch enabled */
PWM0LER = LER0_EN | LER1_EN | LER2_EN | LER3_EN | LER4_EN | LER5_EN | LER6_EN;
}
else if ( ChannelNum == 1 )
{
match_counter1 = 0;
PINSEL4 = 0x00001555; /* set GPIOs for all PWM pins on PWM0 */
PWM1TCR = TCR_RESET; /* Counter Reset */
PWM1PR = 0x00; /* count frequency:Fpclk */
PWM1MCR = PWMMR0I | PWMMR0R; /* interrupt on PWMMR0, reset on PWMMR0, reset
TC if PWM0 matches */
PWM1MR0 = cycle; /* set PWM cycle */
PWM1MR1 = cycle * 5/6;
PWM1MR2 = cycle * 2/3;
PWM1MR3 = cycle * 1/2;
PWM1MR4 = cycle * 1/3;
PWM1MR5 = cycle * 1/6;
/* all PWM latch enabled */
PWM1LER = LER0_EN | LER1_EN | LER2_EN | LER3_EN | LER4_EN | LER5_EN | LER6_EN;
}
else
{
return ( FALSE ); /* Unknown channel number */
}
if ( install_irq( PWM0_1_INT, (void *)PWMHandler, HIGHEST_PRIORITY ) == FALSE )
{
return ( FALSE );
}
return (TRUE);
}
/******************************************************************************
** Function name: PWM_Set
**
** Descriptions: PWM cycle setup
**
** parameters: Channel number, PWM cycle, and offset
** Returned value: None
**
******************************************************************************/
void PWM_Set( DWORD ChannelNum, DWORD cycle, DWORD offset )
{
if ( ChannelNum == 0 )
{
PWM0MR0 = cycle; /* set PWM cycle */
PWM0MR1 = cycle * 5/6 + offset;
PWM0MR2 = cycle * 2/3 + offset;
PWM0MR3 = cycle * 1/2 + offset;
PWM0MR4 = cycle * 1/3 + offset;
PWM0MR5 = cycle * 1/6 + offset;
/* The LER will be cleared when the Match 0 takes place, in order to
load and execute the new value of match registers, all the PWMLERs need to
reloaded. all PWM latch enabled */
PWM0LER = LER0_EN | LER1_EN | LER2_EN | LER3_EN | LER4_EN | LER5_EN | LER6_EN;
}
else if ( ChannelNum == 1 )
{
PWM1MR0 = cycle; /* set PWM cycle */
PWM1MR1 = cycle * 5/6 + offset;
PWM1MR2 = cycle * 2/3 + offset;
PWM1MR3 = cycle * 1/2 + offset;
PWM1MR4 = cycle * 1/3 + offset;
PWM1MR5 = cycle * 1/6 + offset;
/* The LER will be cleared when the Match 0 takes place, in order to
load and execute the new value of match registers, all the PWMLERs need to
reloaded. all PWM latch enabled */
PWM1LER = LER0_EN | LER1_EN | LER2_EN | LER3_EN | LER4_EN | LER5_EN | LER6_EN;
}
return;
}
/******************************************************************************
** Function name: PWM_Start
**
** Descriptions: Enable PWM by setting the PCR, PTCR registers
**
** parameters: channel number
** Returned value: None
**
******************************************************************************/
void PWM_Start( DWORD channelNum )
{
if ( channelNum == 0 )
{
/* All single edge, all enable */
PWM0PCR = PWMENA1 | PWMENA2 | PWMENA3 | PWMENA4 | PWMENA5 | PWMENA6;
PWM0TCR = TCR_CNT_EN | TCR_PWM_EN; /* counter enable, PWM enable */
}
else if ( channelNum == 1 )
{
/* All single edge, all enable */
PWM1PCR = PWMENA1 | PWMENA2 | PWMENA3 | PWMENA4 | PWMENA5 | PWMENA6;
PWM1TCR = TCR_CNT_EN | TCR_PWM_EN; /* counter enable, PWM enable */
}
return;
}
/******************************************************************************
** Function name: PWM_Stop
**
** Descriptions: Stop all PWM channels
**
** parameters: channel number
** Returned value: None
**
******************************************************************************/
void PWM_Stop( DWORD channelNum )
{
if ( channelNum == 0 )
{
PWM0PCR = 0;
PWM0TCR = 0x00; /* Stop all PWMs */
}
else if ( channelNum == 1 )
{
PWM1PCR = 0;
PWM1TCR = 0x00; /* Stop all PWMs */
}
return;
}
