#include "weigh.h"

//10000記數(shù) = 10kg=10000g
#define CAL_MIN_MAX_SPAN    10000 

#define BRIDGE_SUPPLY       (BIT0 | BIT1)
#define PUSH_BUTTON         BIT0
int nStart;
int ad_flag;

void Init_Sys(void)
{
    //停止看門狗
    WDTCTL = WDTPW + WDTHOLD;
    //設(shè)置晶體的電容
    FLL_CTL0 |= XCAP18PF;

    //定時(shí)器的中斷為0.5s
    BTCTL = BTDIV + BT_fCLK2_DIV64;
    //定時(shí)器中斷使能
    IE2 |= BTIE;
  
    //P1口輸出為1
    P1OUT = 0xff;  
    //P1口為輸出方向
    P1DIR = 0xff;
    //P1.0為輸入方向
    P1DIR &= ~PUSH_BUTTON;
    //下降沿觸發(fā)中斷
    P1IES = PUSH_BUTTON;
    //清除中斷標(biāo)志
    P1IFG = 0;
    //使能P1.0中斷
    P1IE = PUSH_BUTTON; 
    //P2口輸出為1
    P2OUT = 0xff;
    //P2口為輸出方向
    P2DIR = 0xff;
  
    //SD16設(shè)置
    //增益為32，信道對(duì)為A0+，A0-
    SD16INCTL0 = SD16GAIN_32 + SD16INCH_0; 
    //連續(xù)轉(zhuǎn)換方式
    //SD16轉(zhuǎn)換中斷使能
    SD16CCTL0 = SD16DF + SD16IE; 
        
}
void StartNextConversion(void)
{
    //結(jié)果清零
    SD16Temp = 0;
    SD16TempCtr = 0;
    //對(duì)全橋傳感器供電
    P2OUT |= BRIDGE_SUPPLY; 
    //允許電壓的設(shè)置時(shí)間,(46+4)x244us=12ms
    VoltageSettleCtr = 46;
                
    //開始轉(zhuǎn)換
    SD16CCTL0 |= SD16SC;
}

#if __VER__ < 200
    interrupt [SD16_VECTOR] void SD16_ISR(void)
#else
    #pragma vector=SD16_VECTOR
    __interrupt void SD16_ISR(void)
#endif
{
    long CurrentResult;
  
    //讀轉(zhuǎn)換結(jié)果
    SD16CCTL0 &= ~SD16LSBACC; 
    CurrentResult = (long)(int)SD16MEM0 << 2; 
    SD16CCTL0 |= SD16LSBACC;
    CurrentResult |= ((int)SD16MEM0 & 0xc0) >> 6;
    
    //等待電壓設(shè)置
    if(VoltageSettleCtr)  
    {
        //減數(shù)
        VoltageSettleCtr--;
        return;
    }
  
    //累加求和
    SD16Temp += CurrentResult; 
  
    //是否采集了256次
    if(++SD16TempCtr >= 256)
    {
        //設(shè)置轉(zhuǎn)換完成標(biāo)志
        ad_flag = 1;
        //結(jié)果清零
        SD16TempCtr = 0;
        //累加結(jié)果除以256得到轉(zhuǎn)換結(jié)果的平均數(shù)
        SD16Result = SD16Temp >> 8;
        //禁止轉(zhuǎn)換
        SD16CCTL0 &= ~SD16SC;
        //停止對(duì)全橋傳感器供電
        P2OUT &= ~(BRIDGE_SUPPLY); 
        
        //存儲(chǔ)新的轉(zhuǎn)換結(jié)果
        LastADCValue = SD16Result;
        //進(jìn)入LPM3低功耗模式
        __bis_SR_register_on_exit(LPM3_bits); 
    }
}

#if __VER__ < 200
    interrupt [PORT1_VECTOR] void PORT1_ISR(void)
#else
    #pragma vector=PORT1_VECTOR
    __interrupt void PORT1_ISR(void)
#endif
{
    volatile unsigned int i;

    //是否有按鍵按下？
    if(P1IFG & BIT0)
    {    	
        //清除中斷標(biāo)志位
    	P1IFG &= ~(BIT0);
    }
    //延遲一點(diǎn)時(shí)間
    for (i = 0x7fff; i; i--);                    
    __bic_SR_register_on_exit(SCG1 + SCG0);
}
void main(void)
{ 
    long ad_value;
    //關(guān)閉中斷
    _DINT();
    //初始化
    Init_Sys();
    //初始化變量
    nStart = 0;
    
    //打開中斷
    _EINT();
    
    //循環(huán)處理
    for(;;)
    {
        //測量按紐按下
        if(nStart == 1)
        {
            //清除標(biāo)志
            nStart = 0;            
            //開啟轉(zhuǎn)換
            StartNextConversion();
            
            //轉(zhuǎn)換完成
            if(ad_flag == 1)
            {
                //清除標(biāo)志
                ad_flag = 0;
                ad_value = LastADCValue;
            }
        }
    }
}