HT1381是台湾HT公司的一款串行实时时钟IC，作业电压：2.0V~5.5V，最大输入串行时钟500kHz（VDD=2V），2MHz（VDD=5V） ；作业电流：2V时小于300nA，5V时小于1mA。串行I/O传送，二种数据传送方法：单字节或多字节（Burst方法），一切寄存器以BCD码格局存储
具有接口简略、功耗低、作业电压规模宽、计时准确、功用全、本钱低一级长处，
因此在实践使用中被广泛选用。
该芯片供给秒、分、时、日、日期、月和年的信息。
关于小于31天的月的月末日期能主动进行调整，还包含闰年校对功用。低功耗规划且时钟的运转能够选用24小时格局或带AM/PM指示的12小时的格局。
以下是接口程序，430测验频率为4M.
#define NOP _NOP();_NOP()
#define NowSec cNowTime[0]
#define NowMin cNowTime[1]
#define NowHour cNowTime[2]
#define NowDate cNowTime[3]
#define NowMonth cNowTime[4]
#define NowYear cNowTime[5]
#define SetSec cSetTime[0]
#define SetMin cSetTime[1]
#define SetHour cSetTime[2]
#define SetDate cSetTime[3]
#define SetMonth cSetTime[4]
#define SetYear cSetTime[5]
uchar Temp_Count;
uchar cSetTime[6];
uchar cNowTime[6];
voidTimer_Out_Byte(uchar OutByte);
uchar Timer_In_Byte(void);
void ReadRealtime(void)
{
NOP;
HT1381_OUTPORT &=~Timer_SCL; //Timer_SCL=0;
NOP;
HT1381_OUTPORT |= Timer_Rest; //Timer_Rest=1;
Timer_Out_Byte(0xBF); //Read, Burst Mode
for(TimeCount=0;TimeCount<6;TimeCount++)
{
if(TimeCount==5)
Timer_In_Byte(); //dummy read.
cNowTime[TimeCount]=Timer_In_Byte();
//change BCD to uchar
cNowTime[TimeCount]=(cNowTime[TimeCount]/0x10)*10+(cNowTime[TimeCount]%0x10);
}
NOP;
HT1381_OUTPORT &=~Timer_Rest; //Timer_Rest=0;
}
void WriteRealtime(void)
{
NOP;
HT1381_OUTPORT &=~Timer_Rest; //Timer_Rest=0; //for sure to close rest.
NOP;
HT1381_OUTPORT &=~Timer_SCL; //Timer_SCL=0;
NOP;
HT1381_OUTPORT |= Timer_Rest; //Timer_Rest=1;
Timer_Out_Byte(0x8E); //Write,Single Mode
Timer_Out_Byte(0x00); //Write, Protect Byte=0, Disable protect
NOP;
HT1381_OUTPORT &=~Timer_Rest; //Timer_Rest=0;
NOP;
HT1381_OUTPORT |= Timer_Rest; //Timer_Rest=1;
Timer_Out_Byte(0x80); //Write,Single Mode
Timer_Out_Byte(0x00); //Write, OSC enalbe, old second distroied
NOP;
HT1381_OUTPORT &=~Timer_Rest; //Timer_Rest=0;
for(TimeCount=0;TimeCount<6;TimeCount++)
{
//change uchar to BCD
cSetTime[TimeCount]=(cSetTime[TimeCount]/10)*0x10+(cSetTime[TimeCount]%10);
}
NOP;
HT1381_OUTPORT |= Timer_Rest; //Timer_Rest=1;
Timer_Out_Byte(0XBE); //Write,Burst Mode
Timer_Out_Byte(SetSec & 0x7F); //OSC enable for sure.
Timer_Out_Byte(SetMin);
Timer_Out_Byte(SetHour & 0x7F); //24 Hour Mode
Timer_Out_Byte(SetDate);
Timer_Out_Byte(SetMonth);
Timer_Out_Byte(0x00);
Timer_Out_Byte(SetYear);
Timer_Out_Byte(0x00);
NOP;
HT1381_OUTPORT &=~Timer_Rest; //Timer_Rest=0;
NOP;
HT1381_OUTPORT |= Timer_Rest; //Timer_Rest=1;
Timer_Out_Byte(0x8E); //Write,Single Mode
Timer_Out_Byte(0x80); //Write, Protect Byte=0, enable protect
NOP;
HT1381_OUTPORT &=~Timer_Rest; //Timer_Rest=0;
}
void Timer_Out_Byte(uchar OutByte)
{
uchar Timer_Count;
for (Timer_Count=0;Timer_Count<8;Timer_Count++)
{
HT1381_DIRPORT |= Timer_SDA; //output
if ((OutByte & 0x01) == 0)
HT1381_OUTPORT &=~Timer_SDA;
else
HT1381_OUTPORT |= Timer_SDA;
NOP;
HT1381_OUTPORT |= Timer_SCL;
NOP;
HT1381_OUTPORT &=~Timer_SCL; //Timer_SCL=0;
OutByte = OutByte >> 1;
}
}
uchar Timer_In_Byte(void)
{
uchar InByte,Timer_Count;
InByte=0x00;
HT1381_DIRPORT &=~Timer_SDA; //Timer_SDA=1;//input
for (Timer_Count=0;Timer_Count<8;Timer_Count++)
{
InByte >>= 1;
NOP;
HT1381_OUTPORT |= Timer_SCL;
if(HT1381_INPORT&Timer_SDA)
InByte |= 0x80;
else
InByte &= 0x7F;
NOP;
HT1381_OUTPORT &=~Timer_SCL; //Timer_SCL=0;
}
return(InByte);
}
#define NOP _NOP();_NOP()
#define NowSec cNowTime[0]
#define NowMin cNowTime[1]
#define NowHour cNowTime[2]
#define NowDate cNowTime[3]
#define NowMonth cNowTime[4]
#define NowYear cNowTime[5]
#define SetSec cSetTime[0]
#define SetMin cSetTime[1]
#define SetHour cSetTime[2]
#define SetDate cSetTime[3]
#define SetMonth cSetTime[4]
#define SetYear cSetTime[5]
uchar Temp_Count;
uchar cSetTime[6];
uchar cNowTime[6];
voidTimer_Out_Byte(uchar OutByte);
uchar Timer_In_Byte(void);
void ReadRealtime(void)
{
NOP;
HT1381_OUTPORT &=~Timer_SCL; //Timer_SCL=0;
NOP;
HT1381_OUTPORT |= Timer_Rest; //Timer_Rest=1;
Timer_Out_Byte(0xBF); //Read, Burst Mode
for(TimeCount=0;TimeCount<6;TimeCount++)
{
if(TimeCount==5)
Timer_In_Byte(); //dummy read.
cNowTime[TimeCount]=Timer_In_Byte();
//change BCD to uchar
cNowTime[TimeCount]=(cNowTime[TimeCount]/0x10)*10+(cNowTime[TimeCount]%0x10);
}
NOP;
HT1381_OUTPORT &=~Timer_Rest; //Timer_Rest=0;
}
void WriteRealtime(void)
{
NOP;
HT1381_OUTPORT &=~Timer_Rest; //Timer_Rest=0; //for sure to close rest.
NOP;
HT1381_OUTPORT &=~Timer_SCL; //Timer_SCL=0;
NOP;
HT1381_OUTPORT |= Timer_Rest; //Timer_Rest=1;
Timer_Out_Byte(0x8E); //Write,Single Mode
Timer_Out_Byte(0x00); //Write, Protect Byte=0, Disable protect
NOP;
HT1381_OUTPORT &=~Timer_Rest; //Timer_Rest=0;
NOP;
HT1381_OUTPORT |= Timer_Rest; //Timer_Rest=1;
Timer_Out_Byte(0x80); //Write,Single Mode
Timer_Out_Byte(0x00); //Write, OSC enalbe, old second distroied
NOP;
HT1381_OUTPORT &=~Timer_Rest; //Timer_Rest=0;
for(TimeCount=0;TimeCount<6;TimeCount++)
{
//change uchar to BCD
cSetTime[TimeCount]=(cSetTime[TimeCount]/10)*0x10+(cSetTime[TimeCount]%10);
}
NOP;
HT1381_OUTPORT |= Timer_Rest; //Timer_Rest=1;
Timer_Out_Byte(0XBE); //Write,Burst Mode
Timer_Out_Byte(SetSec & 0x7F); //OSC enable for sure.
Timer_Out_Byte(SetMin);
Timer_Out_Byte(SetHour & 0x7F); //24 Hour Mode
Timer_Out_Byte(SetDate);
Timer_Out_Byte(SetMonth);
Timer_Out_Byte(0x00);
Timer_Out_Byte(SetYear);
Timer_Out_Byte(0x00);
NOP;
HT1381_OUTPORT &=~Timer_Rest; //Timer_Rest=0;
NOP;
HT1381_OUTPORT |= Timer_Rest; //Timer_Rest=1;
Timer_Out_Byte(0x8E); //Write,Single Mode
Timer_Out_Byte(0x80); //Write, Protect Byte=0, enable protect
NOP;
HT1381_OUTPORT &=~Timer_Rest; //Timer_Rest=0;
}
void Timer_Out_Byte(uchar OutByte)
{
uchar Timer_Count;
for (Timer_Count=0;Timer_Count<8;Timer_Count++)
{
HT1381_DIRPORT |= Timer_SDA; //output
if ((OutByte & 0x01) == 0)
HT1381_OUTPORT &=~Timer_SDA;
else
HT1381_OUTPORT |= Timer_SDA;
NOP;
HT1381_OUTPORT |= Timer_SCL;
NOP;
HT1381_OUTPORT &=~Timer_SCL; //Timer_SCL=0;
OutByte = OutByte >> 1;
}
}
uchar Timer_In_Byte(void)
{
uchar InByte,Timer_Count;
InByte=0x00;
HT1381_DIRPORT &=~Timer_SDA; //Timer_SDA=1;//input
for (Timer_Count=0;Timer_Count<8;Timer_Count++)
{
InByte >>= 1;
NOP;
HT1381_OUTPORT |= Timer_SCL;
if(HT1381_INPORT&Timer_SDA)
InByte |= 0x80;
else
InByte &= 0x7F;
NOP;
HT1381_OUTPORT &=~Timer_SCL; //Timer_SCL=0;
}
return(InByte);
}
