//-----------------------------------------------------------------
//  名稱: 三端可調正電壓穩壓器LM317應用測試
//-----------------------------------------------------------------
//  說明: 本例運行時,通過兩個按鍵可實現1.5V~9.0V的直流電壓步進調節,
//        步進值為0.5V,輸出電壓值將同時顯示在7406驅動的數碼管上.
//
//-----------------------------------------------------------------
#include <pic.h> 
#define INT8U  unsigned char
#define INT16U unsigned int
#define _XTAL_FREQ 1000000UL

#define K1 RD6
#define K2 RD7
//0-9的數碼管段碼,最后3位是黑屏及"dC"的段碼,索引為10,11,12
const INT8U SEG_CODE[] =
{ 0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90,0xFF,0xA1,0xC6};

//待顯示數據
INT8U Disp_Buff[] = {11,12,10,0,0,0};
//------------------------------------------------------------------
// 主程序
//------------------------------------------------------------------
void main() 
{ 
    INT8U volt = 0, Disp_Volt = 0, PreKey = 0xFF;
    TRISB = TRISC = 0x00;                   //RB,RC端口均設為輸出
    PORTB = PORTC = 0xFF;                   //初始時關閉數碼管
    TRISD = 0xF0;                           //高四位輸入,低四位輸出
    PORTD = 0xFF;
    PSA = 0;                                //前分頻分配給TMR0
    PS2 = 0; PS1 = PS0 = 1;                 //16分頻(OPTION低3位為011)
    TMR0 = (INT8U)(256 - _XTAL_FREQ/4/16*0.004); //4ms定時初值    
    T0IF = 0;                               //清TMR0中斷標志
    T0CS = 0;                               //TMR0工作于定時器方式
    T0IE = 1;                               //允許TMR0溢出中斷
    GIE = 1;                                //開全局中斷
    while (1)
    {
        if ((PORTD & 0B11000000) != PreKey)
        {
            

        }
    }
} 

//-----------------------------------------------------------------
// TMR0定時器溢出中斷控制數碼管顯示
//-----------------------------------------------------------------
void interrupt TMR0_Refresh_DSY( )
{
    static INT8U i = 0; 
    if (T0IF)
    {
        

    }
}