第一次使用学习单片机编程, 使用了n76e003， 主要在检测pwm的信号问题上花了比较多的时间，最后是使用了timer2的0通道来捕捉上升缘，1通道来捕捉下降缘来检测pwm的宽度。

接收机是0-2000us pwm输出，500-1000是基础的pwm, 就是说没有信号也定期输出500（舵机）或1000（油门），这样单片机可以检测到有无信号.

timer0来控制led的开关和闪烁，timer0使用10khz， timer2使用16m的时钟.

 

#include "N76E003.h"
#include "Common.h"
#include "Delay.h"
#include "SFR_Macro.h"
#include "Function_define.h"


unsigned int pulse_width = 0;
unsigned char rising_cap=1;

#define LED_OFF 0
#define LED_FLASH_SLOW 1
#define LED_FLASH_NORMAL 2
#define LED_FLASH_FAST 3
#define LED_FLASH_ALL_FAST 4

unsigned char led_mod =0;
unsigned int tick;
UINT8 u8TH0_Tmp,u8TL0_Tmp;

/************************************************************************************************************
*    TIMER 0 interrupt subroutine
************************************************************************************************************/
void Timer0_ISR (void) interrupt 1  //interrupt address is 0x000B
{
	
	 // interrupt every 10ms
	  //clr_TF0;
    TH0 = u8TH0_Tmp;
    TL0 = u8TL0_Tmp;    
    tick++;
	 
		
		switch(led_mod)
		{
			case LED_FLASH_SLOW:
				//one 1/4 second
			  if(tick < 25)
				{
					set_P01;
				 
				}
				else 
				{
				
					clr_P01;
				}
				 set_P00;
					set_P02;
				break;
			/*
			case LED_FLASH_NORMAL:
				break;
			case LED_FLASH_FAST:
				break;
			case LED_FLASH_ALL_FAST:
				break;*/
			default:
					{
					clr_P00;
					clr_P01;
					clr_P02;
				}
					break;
		}
		
		if(tick>150)
		{
			tick = 0;	
	  }
	  
}

/************************************************************************************************************
*    Timer2 Capture interrupt subroutine
************************************************************************************************************/

void Capture_ISR (void) interrupt 12
{
	
	
	 if(CAPCON0 & 0x01)
  {
    clr_CAPF0;   
  }
  if(CAPCON0 & 0x02)
  {
    clr_CAPF1;                   
    pulse_width = C1H;
    pulse_width <<= 8;
    pulse_width |= C1L;
		
		if(pulse_width>24000) //1/16m = 0.0000000625   * 24000  ==1500
		{
			led_mod = LED_FLASH_SLOW;
				//set_P00;
		}
		else
		{
			 led_mod = LED_OFF;
		//	clr_P00;
		}
			
  }
}


/************************************************************************************************************
*    Main function 
************************************************************************************************************/
void main (void)
{
		Set_All_GPIO_Quasi_Mode;
		//		InitialUART0_Timer3(115200);
		P05_Input_Mode; //PWM Input
		P00_PushPull_Mode;
		P01_PushPull_Mode;
		P02_PushPull_Mode;

		clr_P00; 
    clr_P01;
	  clr_P02;

		TIMER0_MODE1_ENABLE;
		clr_T0M;  //set div 12  10khz mode;

		u8TH0_Tmp = TIMER_DIV12_VALUE_10ms/256; //every 10 ms
		u8TL0_Tmp = TIMER_DIV12_VALUE_10ms%256;   //every 10 ms 
		TH0 =  u8TH0_Tmp;  //set time out 
		TL0 = u8TL0_Tmp;   

		TIMER2_CAP0_Capture_Mode; 
		IC6_P05_CAP0_RisingEdge_Capture;
		IC6_P05_CAP1_FallingEdge_Capture;


		set_ET0;                                    //enable Timer0 interrupt

		set_ECAP;                                   //Enable Capture interrupt

		set_EA;
		set_TR0;                                    //Timer0 run
		set_TR2;                                    //Triger Timer2


		while(1);
}