SPI的读写GT21L字库芯片

void spi_init(void)  {     uint8 data;

    DDRB |= (1<<MOSI)|(1<<SCK)|(1<<SS)&(~(1<<MISO));        //设置MOSI,SCK,SS为输出,MISO为输入 PORTB |= (1<<MISO)|(1<<SS);                //使能MISO上拉电阻有效     SPCR = (1<<SPE)|(1<<MSTR);                 //SPI使能，MSB，主机，SPI Mode 0SCK=Fosc/4 SPSR = 0x00; data = SPSR;    data = SPDR;   }  void spi_send_byte(char data)    {    SPDR = data; while(!(SPSR & (1<<SPIF)));                //等待数据传输结束  }  char spi_receive_byte(void)  {     char data; SPDR = 0xff;    while(!(SPSR & (1<<SPIF)));                //等待数据接收结束  data = SPDR;  return data;  }  void HighSpeed_Read_GT21L(uint32 address,char *buf,uint32 length)  {      SS_L();      spi_send_byte(0x0B);                     //0x0b快速读取方式      spi_send_byte(((address&0xFFFFFF)>>16)); //3个字节的地址      spi_send_byte(((address&0xFFFF)>>8));      spi_send_byte(address&0xFF);      spi_send_byte(0xFF);                      //dummy字节                                                       while(length--)   {     *(buf++)=spi_receive_byte();   }   SS_H();  }   void Read_Font_GT21L16W(uint8 font_type, uint8 hzzf_h, uint8 hzzf_l, char *dot )  { uint8 temp[2];// uint8 hzzf_h,hzzf_l; uint16  index_addr; uint32  addr;// hzzf_h = (uint8)((srcCode)>>8); // hzzf_l = (uint8)((srcCode)&0xff);    uint16 srcCode; srcCode = (uint16)hzzf_h<<8+hzzf_l; switch(font_type)    {     case  GB12345:           if(((hzzf_h>=0xa1)&&(hzzf_h<=0xa9))&&(hzzf_l>=0xa1))              addr = ((((uint32)hzzf_h)-0xa1)*94 + (((uint32)hzzf_l)-0xa1))*32 + ((uint32)BaseAdd);           else if(((hzzf_h>=0xb0)&&(hzzf_h<=0xf9))&&(hzzf_l>=0xa1))              addr = ((((uint32)hzzf_h)-0xb0)*94 + (((uint32)hzzf_l)-0xa1)+1038)*32 + ((uint32)BaseAdd);           else        return;                HighSpeed_Read_GT21L(addr ,dot, 32);                break;             case  BIG5:        if((hzzf_h>=0xa1)&&((hzzf_l>=0x40)&&(hzzf_l<=0x7e)))          {         index_addr = (hzzf_h-0xa1)*157+(hzzf_l-0x40);          }        else if((hzzf_h>=0xa1)&&((hzzf_l>=0xa1)&&(hzzf_l<=0xfe)))          {         index_addr = (hzzf_h-0xa1)*157+(hzzf_l-0xa1)+63;          }        else       return;          addr = Big5Table+(index_addr*2);        HighSpeed_Read_GT21L(addr,temp,2);        addr = BaseAdd+(((uint32)temp[0]<<8)+temp[1])*32;        HighSpeed_Read_GT21L(addr,dot,32);         break;                case  JIS0208:        if(((hzzf_h>=1)&&(hzzf_h<=89))&&((hzzf_l>=1)&&(hzzf_l<=94)))          {               index_addr = (hzzf_h-1)*94+(hzzf_l-1); //        index_addr = ((((hzzf_h&0xf0)>>4)*10+(hzzf_h&0x0f))-1)*94+(((hzzf_l&0xf0)>>4)*10+(hzzf_l&0x0f))-1;          }        else       return;          addr = JISTable+(index_addr*2);        HighSpeed_Read_GT21L(addr,temp,2);        addr = BaseAdd+(((uint32)temp[0]<<8)+temp[1])*32;        HighSpeed_Read_GT21L(addr,dot,32);             break;    case  ASCLL:     if((hzzf_h==0x00)&&((hzzf_l>=0x20)&&(hzzf_l<=0x7e)))       addr = (hzzf_l-0x20)*16+ASCLL16;     else       return;     HighSpeed_Read_GT21L(addr,dot,16);      break;  case  LDUNICODE:     if((srcCode>=0x00a0)&&(srcCode<=0x0217))       addr = (srcCode-0x00a0)*16+LDTable;     else       return;     HighSpeed_Read_GT21L(addr,dot,16);     break;  case  XLUNICODE:     if((srcCode>=0x0370)&&(srcCode<=0x03cf))       addr = (srcCode-0x00a0)*16+XLTable;     else       return;     HighSpeed_Read_GT21L(addr,dot,16);     break;  case  JLEUNICODE:     if((srcCode>=0x0400)&&(srcCode<=0x04f9))       addr = (srcCode-0x0400)*16+JLETable;     else       return;     HighSpeed_Read_GT21L(addr,dot,16);     break;                 default:        break;      }     }