LCD2002开机显示偶尔乱码

只看该作者 · 2019-1-2 13:38

#define adress_1602 0x4e
unsigned char ack1;
unsigned char LCD_data=0x08;

void Start()
{
      SDA1=1;
      _nop_();
      SCL1=1;
      nop4();
      SDA1=0;
      nop4();
      SCL1=0;
      _nop_();
      _nop_();
}

void Stop()
{
      SDA1=0;
      _nop_();
      SCL1=0;
      nop4();//>4us后SCL跳变
      SCL1=1;
      nop4();
      SDA1=1;
      _nop_();
      _nop_();
}
void  Write_A_Byte(unsigned char c)
{
   unsigned char BitCnt;
   for(BitCnt=0;BitCnt<8;BitCnt++)  //要传送的数据长度为8位
      {
      if((c<<BitCnt)&0x80)  SDA1=1; //判断发送位
      else  SDA1=0;
      _nop_();
      SCL1=1;             //置时钟线为高，通知被控器开始接收数据位
      nop4();
      _nop_();
      SCL1=0;
      }
      _nop_();
      _nop_();
      SDA1=1;             //8位发送完后释放数据线，准备接收应答位
      _nop_();
      _nop_();
      SCL1=1;
      _nop_();
      _nop_();
      _nop_();
      if(SDA1==1)
ack1=0;
      else
ack1=1;       //判断是否接收到应答信号
      SCL1=0;
      _nop_();
      _nop_();
}

只看该作者 · 2019-1-2 13:40

unsigned char Write_Random_Address_Byte(unsigned char add,unsigned char dat)
{
      Start(); //启动总线
      Write_A_Byte(add); //发送器件地址
      if(ack1==0)return(0);
      Write_A_Byte(dat); //发送数据
      if(ack1==0)return(0);
      Stop(); //结束总线
      return(1);
}
void Enable_LCD_write()
{
      LCD_data|=(1<<(3-1));//E=1;
      Write_Random_Address_Byte(adress_1602,LCD_data);  //
      delay_nus(2);
      LCD_data&=~(1<<(3-1));//E=0;
      Write_Random_Address_Byte(adress_1602,LCD_data);
}
void LCD_Write_Com(unsigned char command)
{
      delay_nus(16);
      LCD_data&=~(1<<(1-1));//RS=0;
      LCD_data&=~(1<<(2-1));//RW=0;
      //LCD_data&=~(1<<(4-1));
      Write_Random_Address_Byte(adress_1602,LCD_data);

      LCD_data&=0X0f; //清高四位
      LCD_data|=command & 0xf0; //写高四位
      Write_Random_Address_Byte(adress_1602,LCD_data);
      Enable_LCD_write();

      command=command<<4; //低四位移到高四位
      LCD_data&=0x0f; //清高四位
      LCD_data|=command&0xf0; //写低四位
      Write_Random_Address_Byte(adress_1602,LCD_data);
      Enable_LCD_write();
}
void LCD_Write_Data(unsigned char value)
{
      delay_nus(16);
      LCD_data|=(1<<(1-1));//RS=1;
      LCD_data&=~(1<<(2-1));//RW=0;
      Write_Random_Address_Byte(adress_1602,LCD_data);

      LCD_data&=0X0f; //清高四位
      LCD_data|=value&0xf0; //写高四位
      Write_Random_Address_Byte(adress_1602,LCD_data);
      Enable_LCD_write();

      value=value<<4; //低四位移到高四位
      LCD_data&=0x0f; //清高四位
      LCD_data|=value&0xf0; //写低四位
      Write_Random_Address_Byte(adress_1602,LCD_data);
      Enable_LCD_write();
}
void LCD_Clear(void)
{
LCD_Write_Com(0x01);
delay_nms(2);
}
/*------------------------------------------------
            写入字符串函数
------------------------------------------------*/
void LCD_Write_String(unsigned char x,unsigned char y,unsigned char *dat,uint8 lg)
{
uint8 i;
#if 1
   if (y == 0)
      {
      LCD_Write_Com(0x80 + x);    //表示第一行
      }
   else
      {
      LCD_Write_Com(0xC0 + x);    //表示第二行
      }
   for(i=0;i<lg && *dat!='\0';i++)
{
LCD_Write_Data(*(dat++));
}
#endif
}
void LCD_Init(void)
{
LCD_Write_Com(0x02);
delay_nus(40);
LCD_Write_Com(0x28); //4位显示！！！！！！！！！！！！！！！！！！
LCD_Write_Com(0x0c); //显示开
LCD_Write_Com(0x01); //清屏
delay_nms(10);
}