//=====================================================================
//TLV5618驅動及簡單測試例子(三角波產(chǎn)生程序,波形頂部不大好)
//IOB15-->DIN
//IOB14-->SCLK
//IOB13-->CS
//DATA15--DATA12分別為:R1.SPD.PWR.R0
//R1R0:00 Write data to DAC B and BUFFER
//     01 Write data to BUFFER
//           10 Write data to DAC A and update DAC B with BUFFER content
//     11 Reserved
//SPD: Speed control bit  1  fast mode 0  slow mode
//PWR: Power control bit  1  power down 0  normal operation
//On power up, SPD and PWD are reset to 0 (slow mode and normal operation)
//參考電壓應小于VDD-3.3伏
//輸出模擬電壓為:V=2*Vref*(dignum/0x1000) 注:dignum后四位為:0x0000~~0x0fff
//
//注:所需輸入的數(shù)字信號值為16位數(shù),其中D15~~D12為特殊位設置,如上面說明
//   D11~~D0為數(shù)據(jù)位000~~fff
//
//***********done by:murufy 2007.8.8于EDA實驗室***********************
//=====================================================================
#define                P_Watchdog_Clear                (volatile unsigned int *)0x7012
#define                P_IOA_Data                                (volatile unsigned int *)0x7000
#define                P_IOA_Buffer                        (volatile unsigned int *)0x7001
#define                P_IOA_Dir                                (volatile unsigned int *)0x7002
#define                P_IOA_Attrib                        (volatile unsigned int *)0x7003
#define                P_IOA_Latch                                (volatile unsigned int *)0x7004

#define                P_IOB_Data                                (volatile unsigned int *)0x7005
#define                P_IOB_Buffer                        (volatile unsigned int *)0x7006
#define                P_IOB_Dir                                (volatile unsigned int *)0x7007
#define                P_IOB_Attrib                        (volatile unsigned int *)0x7008
//若修改端口可更改此處
#define          P_IO_Data                 *P_IOB_Data                         
#define          P_IO_Buffer             *P_IOB_Buffer                 
#define          P_IO_Dir           *P_IOB_Dir                                 
#define          P_IO_Attrib       *P_IOB_Attrib        
//
#define   DIN   0x8000
#define   SCLK  0x4000
#define   CS    0x2000
//==================================================================
//
//初始化,將三個引腳全設成輸出
//
//==================================================================
void DA_init()
{
        P_IO_Dir=DIN+SCLK+CS;
        P_IO_Attrib=DIN+SCLK+CS;//同相輸出
        
}
//===================================================================
//
//DA_conver()
//Dignum:根據(jù)說明設置轉化數(shù)據(jù).頭四位為特殊位用于選擇轉化方式,以及用于
//       通道選擇.請自行設置.
//===================================================================
void DA_conver(unsigned int Dignum)
{   
        unsigned int i;
        unsigned int Dig;
        P_IO_Buffer|=SCLK;//sclk=1
        P_IO_Buffer&=(~CS);//cs=0;
        for(i=0;i<=15;i++)
        {
                Dig=Dignum&0x8000;                
                if(Dig==0)P_IO_Buffer&=(~DIN);      //DIN=0
                else P_IO_Buffer|=DIN;              //DIN=1
                P_IO_Buffer&=(~SCLK);//sclk=0                
                P_IO_Buffer|=SCLK;                     //sclk=1
                Dignum=Dignum<<1;
        }
        P_IO_Buffer|=SCLK;//cs=1,sclk=1
        P_IO_Buffer|=CS;//cs=1,sclk=1
}
//=====================================================================
//主函數(shù):void main()
//僅供測試用,無實際意義
//通過改變DA_conver(dignum)的參數(shù)來觀察輸出,此程序A通道輸出約3.3伏
//=====================================================================         
int main()
{
        unsigned int mm=0x8000;
        DA_init();
        while(1)
        {
        while(mm!=0x8000)         
                {
                        DA_conver(mm);
                        mm=mm-0x0009;//幅度減小一個臺階
                        *P_Watchdog_Clear=0x0001;
                }             
                while(mm!=0x8fff) 
                { 
                        DA_conver(mm);
                        mm=mm+0x0009; //幅度提高一個臺階
                        *P_Watchdog_Clear=0x0001;
                }
        *P_Watchdog_Clear=0x01;
        }
}