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/**************************************************************************//**
* @file main.c
* @version V1.00
* $Revision: 4 $
* $Date: 15/05/22 2:06p $
* @brief Capture the PWMB Channel 1 waveform by PWMB Channel 2.
*
* @note
* Copyright (C) 2014 Nuvoton Technology Corp. All rights reserved.
*
******************************************************************************/
#include <stdio.h>
#include "M051Series.h"
/*---------------------------------------------------------------------------------------------------------*/
/* Macro, type and constant definitions */
/*---------------------------------------------------------------------------------------------------------*/
#define PLLCON_SETTING CLK_PLLCON_50MHz_HXT
#define PLL_CLOCK 50000000
/**
* @brief PWMA IRQ Handler
*
* @param None
*
* @return None
*
* @details ISR to handle PWMA interrupt event
*/
void PWMA_IRQHandler(void)
{
/*In this sample code, user will not use PWMA channel 0~3 PIIR interrupt and CAPIF capture interrupt.
Defined following code as 0 for reducing interrupt execution time and code size. */
#if 0
uint32_t u32PwmIntFlag, u32CapIntFlag0, u32CapIntFlag1;
/* Handle PWMA Capture function */
u32CapIntFlag0 = PWMA->CCR0;
u32CapIntFlag1 = PWMA->CCR2;
if(u32CapIntFlag0 & PWM_CCR0_CAPIF0_Msk)
{
PWMA->CCR0 &= (PWM_CCR_MASK | PWM_CCR0_CAPIF0_Msk);
}
else if(u32CapIntFlag0 & PWM_CCR0_CAPIF1_Msk)
{
PWMA->CCR0 &= (PWM_CCR_MASK | PWM_CCR0_CAPIF1_Msk);
}
else if(u32CapIntFlag1 & PWM_CCR2_CAPIF2_Msk)
{
PWMA->CCR2 &= (PWM_CCR_MASK | PWM_CCR2_CAPIF2_Msk);
}
else if(u32CapIntFlag1 & PWM_CCR2_CAPIF3_Msk)
{
PWMA->CCR2 &= (PWM_CCR_MASK | PWM_CCR2_CAPIF3_Msk);
}
/* Handle PWMA Timer function */
u32PwmIntFlag = PWMA->PIIR;
if(u32PwmIntFlag & PWM_PIIR_PWMIF0_Msk)
{
PWMA->PIIR = PWM_PIIR_PWMIF0_Msk;
}
else if(u32PwmIntFlag & PWM_PIIR_PWMIF1_Msk)
{
PWMA->PIIR = PWM_PIIR_PWMIF1_Msk;
}
else if(u32PwmIntFlag & PWM_PIIR_PWMIF2_Msk)
{
PWMA->PIIR = PWM_PIIR_PWMIF2_Msk;
}
else if(u32PwmIntFlag & PWM_PIIR_PWMIF3_Msk)
{
PWMA->PIIR = PWM_PIIR_PWMIF3_Msk;
}
#endif
}
/**
* @brief PWMB IRQ Handler
*
* @param None
*
* @return None
*
* @details ISR to handle PWMB interrupt event
*/
void PWMB_IRQHandler(void)
{
// uint32_t u32PwmIntFlag;
uint32_t u32CapIntFlag1;
/* Handle PWMB Capture function */
u32CapIntFlag1 = PWMB->CCR2;
/* PWMB channel 2 Capture interrupt */
if(u32CapIntFlag1 & PWM_CCR2_CAPIF2_Msk)
{
PWMB->CCR2 &= (PWM_CCR_MASK | PWM_CCR2_CAPIF2_Msk);
}
}
/*--------------------------------------------------------------------------------------*/
/* Capture function to calculate the input waveform information */
/* u32Count[4] : Keep the internal counter value when input signal rising / falling */
/* happens */
/* */
/* time A B C D */
/* ___ ___ ___ ___ ___ ___ ___ ___ */
/* ____| |_| |_| |_| |_| |_| |_| |_| |_____ */
/* index 0 1 2 3 */
/* */
/* The capture internal counter down count from 0x10000, and reload to 0x10000 after */
/* input signal falling happens (Time B/C/D) */
/*--------------------------------------------------------------------------------------*/
void CalPeriodTime(PWM_T *PWM, uint32_t u32Ch)
{
uint16_t u32Count[4];
uint32_t u32i;
uint16_t u16RisingTime, u16FallingTime, u16HighPeroid, u16LowPeroid, u16TotalPeroid;
/* Clear Capture Falling Indicator (Time A) */
PWM_ClearCaptureIntFlag(PWM, u32Ch, PWM_CAPTURE_INT_FALLING_LATCH);
/* Wait for Capture Falling Indicator */
while(PWM_GetCaptureIntFlag(PWM, u32Ch) < 2);
/* Clear Capture Falling Indicator (Time B)*/
PWM_ClearCaptureIntFlag(PWM, u32Ch, PWM_CAPTURE_INT_FALLING_LATCH);
u32i = 0;
while(u32i < 4)
{
/* Wait for Capture Falling Indicator */
while(PWM_GetCaptureIntFlag(PWM, u32Ch) < 2);
/* Clear Capture Falling and Rising Indicator */
PWM_ClearCaptureIntFlag(PWM, u32Ch, PWM_CAPTURE_INT_FALLING_LATCH | PWM_CAPTURE_INT_RISING_LATCH);
/* Get Capture Falling Latch Counter Data */
u32Count[u32i++] = PWM_GET_CAPTURE_FALLING_DATA(PWM, u32Ch);
/* Wait for Capture Rising Indicator */
while(PWM_GetCaptureIntFlag(PWM, u32Ch) < 2);
/* Clear Capture Rising Indicator */
PWM_ClearCaptureIntFlag(PWM, u32Ch, PWM_CAPTURE_INT_RISING_LATCH);
/* Get Capture Rising Latch Counter Data */
u32Count[u32i++] = PWM_GET_CAPTURE_RISING_DATA(PWM, u32Ch);
}
u16RisingTime = u32Count[1];
u16FallingTime = u32Count[0];
u16HighPeroid = u32Count[1] - u32Count[2];
u16LowPeroid = 0x10000 - u32Count[1];
u16TotalPeroid = 0x10000 - u32Count[2];
printf("\nPWM generate: \nHigh Period=7199 ~ 7201, Low Period=16799 ~ 16801, Total Period=23999 ~ 24001\n");
printf("\nCapture Result: Rising Time = %d, Falling Time = %d \nHigh Period = %d, Low Period = %d, Total Period = %d.\n\n",
u16RisingTime, u16FallingTime, u16HighPeroid, u16LowPeroid, u16TotalPeroid);
if((u16HighPeroid < 7199) || (u16HighPeroid > 7201) || (u16LowPeroid < 16799) || (u16LowPeroid > 16801) || (u16TotalPeroid < 23999) || (u16TotalPeroid > 24001))
printf("Capture Test Fail!!\n");
else
printf("Capture Test Pass!!\n");
}
void SYS_Init(void)
{
/*---------------------------------------------------------------------------------------------------------*/
/* Init System Clock */
/*---------------------------------------------------------------------------------------------------------*/
/* Enable Internal RC clock */
CLK->PWRCON |= CLK_PWRCON_OSC22M_EN_Msk;
/* Waiting for IRC22M clock ready */
while(!(CLK->CLKSTATUS & CLK_CLKSTATUS_OSC22M_STB_Msk));
/* Switch HCLK clock source to Internal RC and HCLK source divide 1 */
CLK->CLKSEL0 &= ~CLK_CLKSEL0_HCLK_S_Msk;
CLK->CLKSEL0 |= CLK_CLKSEL0_HCLK_S_HIRC;
CLK->CLKDIV &= ~CLK_CLKDIV_HCLK_N_Msk;
/* Set PLL to power down mode and PLL_STB bit in CLKSTATUS register will be cleared by hardware.*/
CLK->PLLCON |= CLK_PLLCON_PD_Msk;
/* Enable external 12MHz XTAL, internal 22.1184MHz */
CLK->PWRCON |= CLK_PWRCON_XTL12M_EN_Msk | CLK_PWRCON_OSC22M_EN_Msk;
/* Enable PLL and Set PLL frequency */
CLK->PLLCON = PLLCON_SETTING;
/* Waiting for clock ready */
while(!(CLK->CLKSTATUS & (CLK_CLKSTATUS_PLL_STB_Msk | CLK_CLKSTATUS_XTL12M_STB_Msk | CLK_CLKSTATUS_OSC22M_STB_Msk)));
/* Switch HCLK clock source to PLL, STCLK to HCLK/2 */
CLK->CLKSEL0 = CLK_CLKSEL0_STCLK_S_HCLK_DIV2 | CLK_CLKSEL0_HCLK_S_PLL;
/* Enable IP clock */
CLK->APBCLK = CLK_APBCLK_UART0_EN_Msk | CLK_APBCLK_PWM45_EN_Msk | CLK_APBCLK_PWM67_EN_Msk;
/* IP clock source */
CLK->CLKSEL1 = CLK_CLKSEL1_UART_S_PLL;
/* IP clock source */
CLK->CLKSEL2 = CLK_CLKSEL2_PWM45_S_HXT | CLK_CLKSEL2_PWM67_S_HXT;
/* Reset PWMB channel0~channel3 */
SYS->IPRSTC2 = SYS_IPRSTC2_PWM47_RST_Msk;
SYS->IPRSTC2 = 0;
/* Update System Core Clock */
/* User can use SystemCoreClockUpdate() to calculate PllClock, SystemCoreClock and CycylesPerUs automatically. */
//SystemCoreClockUpdate();
PllClock = PLL_CLOCK; // PLL
SystemCoreClock = PLL_CLOCK / 1; // HCLK
CyclesPerUs = PLL_CLOCK / 1000000; // For SYS_SysTickDelay()
/*---------------------------------------------------------------------------------------------------------*/
/* Init I/O Multi-function */
/*---------------------------------------------------------------------------------------------------------*/
/* Set P3 multi-function pins for UART0 RXD and TXD */
SYS->P3_MFP = SYS_MFP_P30_RXD0 | SYS_MFP_P31_TXD0;
/* Set P2 multi-function pins for PWMB Channel0~3 */
SYS->P2_MFP = SYS_MFP_P25_PWM5 | SYS_MFP_P26_PWM6;
}
void UART0_Init(void)
{
/*---------------------------------------------------------------------------------------------------------*/
/* Init UART */
/*---------------------------------------------------------------------------------------------------------*/
UART0->BAUD = UART_BAUD_MODE2 | UART_BAUD_MODE2_DIVIDER(PLL_CLOCK, 115200);
UART0->LCR = UART_WORD_LEN_8 | UART_PARITY_NONE | UART_STOP_BIT_1;
}
/*---------------------------------------------------------------------------------------------------------*/
/* Main Function */
/*---------------------------------------------------------------------------------------------------------*/
int32_t main(void)
{
/* Unlock protected registers */
SYS_UnlockReg();
/* Init System, IP clock and multi-function I/O */
SYS_Init();
/* Lock protected registers */
SYS_LockReg();
/* Init UART0 for printf */
UART0_Init();
printf("+------------------------------------------------------------------------+\n");
printf("| PWM Driver Sample Code |\n");
printf("| |\n");
printf("+------------------------------------------------------------------------+\n");
printf(" This sample code will use PWMB channel 2 to capture\n the signal from PWMB channel 1.\n");
printf(" I/O configuration:\n");
printf(" PWM5(P2.5 PWMB channel 1) <--> PWM6(P2.6 PWMB channel 2)\n\n");
printf("Use PWMB Channel 2(P2.6) to capture the PWMB Channel 1(P2.5) Waveform\n");
while(1)
{
printf("Press any key to start PWM Capture Test\n");
getchar();
/*--------------------------------------------------------------------------------------*/
/* Set the PWMB Channel 1 as PWM output function. */
/*--------------------------------------------------------------------------------------*/
/* Assume PWM output frequency is 250Hz and duty ratio is 30%, user can calculate PWM settings by follows.
duty ratio = (CMR+1)/(CNR+1)
cycle time = CNR+1
High level = CMR+1
PWM clock source frequency = __HXT = 12000000
(CNR+1) = PWM clock source frequency/prescaler/clock source divider/PWM output frequency
= 12000000/2/1/250 = 24000
(Note: CNR is 16 bits, so if calculated value is larger than 65536, user should increase prescale value.)
CNR = 23999
duty ratio = 30% ==> (CMR+1)/(CNR+1) = 30%
CMR = 7199
Prescale value is 1 : prescaler= 2
Clock divider is PWM_CSR_DIV1 : clock divider =1
*/
/* set PWMB channel 1 output configuration */
PWM_ConfigOutputChannel(PWMB, PWM_CH1, 250, 30);
/* Enable PWM Output path for PWMB channel 1 */
PWM_EnableOutput(PWMB, 0x2);
/* Enable Timer for PWMB channel 1 */
PWM_Start(PWMB, 0x2);
/*--------------------------------------------------------------------------------------*/
/* Set the PWMB channel 2 for capture function */
/*--------------------------------------------------------------------------------------*/
/* If input minimum frequency is 250Hz, user can calculate capture settings by follows.
Capture clock source frequency = __HXT = 12000000 in the sample code.
(CNR+1) = Capture clock source frequency/prescaler/clock source divider/minimum input frequency
= 12000000/2/1/250 = 24000
(Note: CNR is 16 bits, so if calculated value is larger than 65536, user should increase prescale value.)
CNR = 0xFFFF
(Note: In capture mode, user should set CNR to 0xFFFF to increase capture frequency range.)
*/
/* set PWMB channel 2 capture configuration */
PWM_ConfigCaptureChannel(PWMB, PWM_CH2, 166, 0);
/* Enable capture falling edge interrupt for PWMB channel 2 */
PWM_EnableCaptureInt(PWMB, PWM_CH2, PWM_CAPTURE_INT_FALLING_LATCH);
/* Enable PWMB NVIC interrupt */
NVIC_EnableIRQ((IRQn_Type)(PWMB_IRQn));
/* Enable Timer for PWMB channel 2 */
PWM_Start(PWMB, 0x4);
/* Enable Capture Function for PWMB channel 2 */
PWM_EnableCapture(PWMB, 0x4);
/* Wait until PWMB channel 2 Timer start to count */
while(PWMB->PDR2 == 0);
/* Capture the Input Waveform Data */
CalPeriodTime(PWMB, PWM_CH2);
/*------------------------------------------------------------------------------------------------------*/
/* Stop PWMB channel 1 (Recommended procedure method 1) */
/* Set PWM Timer loaded value(CNR) as 0. When PWM internal counter(PDR) reaches to 0, disable PWM Timer */
/*------------------------------------------------------------------------------------------------------*/
/* Set PWMB channel 1 loaded value as 0 */
PWM_Stop(PWMB, 0x2);
/* Wait until PWMB channel 1 Timer Stop */
while(PWMB->PDR1 != 0);
/* Disable Timer for PWMB channel 1 */
PWM_ForceStop(PWMB, 0x2);
/* Disable PWM Output path for PWMB channel 1 */
PWM_DisableOutput(PWMB, 0x2);
/*------------------------------------------------------------------------------------------------------*/
/* Stop PWMB channel 2 (Recommended procedure method 1) */
/* Set PWM Timer loaded value(CNR) as 0. When PWM internal counter(PDR) reaches to 0, disable PWM Timer */
/*------------------------------------------------------------------------------------------------------*/
/* Disable PWMB NVIC */
NVIC_DisableIRQ((IRQn_Type)(PWMB_IRQn));
/* Set loaded value as 0 for PWMB channel 2 */
PWM_Stop(PWMB, 0x4);
/* Wait until PWMB channel 2 current counter reach to 0 */
while(PWMB->PDR2 != 0);
/* Disable Timer for PWMB channel 2 */
PWM_ForceStop(PWMB, 0x4);
/* Disable Capture Function and Capture Input path for PWMB channel 2*/
PWM_DisableCapture(PWMB, 0x4);
/* Clear Capture Interrupt flag for PWMB channel 2*/
PWM_ClearCaptureIntFlag(PWMB, PWM_CH2, PWM_CAPTURE_INT_FALLING_LATCH);
}
}
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