软件模拟SPI源码.doc

typedefunsignedcharboolean;/*布尔变量*/ typedefunsignedcharuint8;/*无符号8位整型变量*/ typedefsignedcharint8;/*有符号8位整型变量*/ typedefunsignedshortuint16;/*无符号16位整型变量*/ typedefsignedshortint16;/*有符号16位整型变量*/ typedefunsignedintuint32;/*无符号32位整型变量*/ typedefsignedintint32;/*有符号32位整型变量*/ typedeffloatfp32;/*单精度浮点数（32位长度）*/ typedefdoublefp64;/*双精度浮点数（64位长度） #defineR00 #defineR11 #defineR1b2 #defineR23 #defineR34 uint32loop_time; uint8rep5; #definenop()do;while(0); #defineCS_PIN6/RSVD4 #defineDI_PIN7/RWVD6 #defineSD_CS_PORTrPDATE #defineSD_CS_DDR_PORTrPCONE #defineSD_CS_PUP_PORTrPUPE #defineSD_DI_PORTrPDATE #defineSD_DI_DDR_PORTrPCONE #defineSD_DI_PUP_PORTrPUPE #defineDO_PIN12/ENVD5 #defineCLK_PIN13/RSVD4 #defineSD_DO_PORTrPDATC #defineSD_DO_DDR_PORTrPCONC #defineSD_DO_PUP_PORTrPUPC #defineSD_CLK_PORTrPDATC #defineSD_CLK_DDR_PORTrPCONC #defineSD_CLK_PUP_PORTrPUPC #defineCS_LOW()SD_CS_PORT&=(1CS_PIN) #defineCS_HIGH()SD_CS_PORT|=(1CS_PIN) #defineDI_LOW()SD_DI_PORT&=(1DI_PIN) #defineDI_HIGH()SD_DI_PORT|=(1DI_PIN) #defineCLK_LOW()SD_CLK_PORT&=(1CLK_PIN) #defineCLK_HIGH()SD_CLK_PORT|=(1CLK_PIN) #defineDO()SD_DO_PORT&(0x01DO_PIN) #define_400KHZ_128 #define_10MHZ_1 /- /延时 staticvoidloop(uint32i) /- while(i-) ;/nop(); /- /发送一字节数据 staticvoidSPI_send(uint8cmd) /- uint8i; uint8MASK=0x80,0x40,0x20,0x10,0x08,0x04,0x02,0x01; for(i=0;i8;i+) CLK_LOW(); if(cmd&MASKi) DI_HIGH(); else DI_LOW(); loop(loop_time); CLK_HIGH(); /- /接收一字节数据 staticuint8SPI_receive(void) /- uint8i; uint8ret=0; uint8MASK=0x80,0x40,0x20,0x10,0x08,0x04,0x02,0x01; for(i=0;i24); SPI_send(arg16); SPI_send(arg8); SPI_send(arg); SPI_send(0x95); switch(ACK) caseR0: return1; caseR1: len=1; break; caseR2: len=2; break; caseR3: len=5; break; default: return0; break; for(i=0;i=100) SPI_send(0xff); return0; rep0=status; for(i=1;ilen;i+) repi=SPI_receive(); SPI_send(0xff); return1; /- staticvoidReset(void) /- CS_LOW(); SendCommand(0x00,0x00,R0); CS_HIGH(); /- staticuint32IsSD(void) /- uint32i; CS_LOW(); for(i=0;i1000;i+) SendCommand(55,0x0000,R1); SendCommand(41,0x0000,R1); if(!rep0) break; loop(200); CS_HIGH(); returni!=100; /- staticuint32IsMMC(void) /- uint32i; CS_LOW(); for(i=0;i1000;i+) SendCommand(1,0x0000,R1); if(!rep0) break; loop(200); CS_HIGH(); returni!=100; /- intSD_erase(uint32sector,uint8*buff) /- CS_LOW(); if(!SendCommand(32,sector9,R1)|!SendCommand(33,sector9,R1)|!SendCommand(38,0x0000,R1) CS_HIGH(); return0; while(!DO() SPI_send(0xff); CS_HIGH(); return1; uint32SD_read(uint32sector,uint8*buff) uint32i; CS_LOW(); if(!SendCommand(17,sector9,R1) CS_HIGH(); /UART_puts(readerr1); return0; for(i=0;i=100) CS_HIGH(); /UART_puts(readerr2); return0; for(i=0;i512;i+) *buff+=SPI_receive(); SPI_receive(); SPI_receive(); SPI_send(0xff); CS_HIGH(); /UART_puts(readOK); return1; uint32SD_write(uint32sector,uint8*buff) uint32i; CS_LOW(); SendCommand(24,sector9,R1); SPI_send(0xfe); for(i=0;i512;i+) SPI_send(buffi); SPI_send(0xff); SPI_send(0xff); for(i=0;i=100) /UART_puts(writeerr1); return0; while(!DO() SPI_send(0xff); CS_HIGH(); /UART_puts(writeOK); /下面其实是复位 loop_time=_400KHZ_; SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); IsSD(); loop_time=_10MHZ_; /完 return1; voidSD_install(void) loop_time=_400KHZ_; SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); SPI_send(0xff); Reset(); if(!IsSD()&!IsMMC() /UART_puts(unknowncardtype!n); return; /UART_puts(SD/MMCcardfound!nNowloadingSD/MMCdriver.n);