SPI.rar_SPI 读取

//**************************************************************************************** //Chip： SST25VF016B //Control mode：SPI //Capacity： 2M x 8bit 0x0000~0x1FFF //**************************************************************************************** //**************************************************************************************** //提取外扩flash数据，将提取的数据转交给上层 //第一层，上层为Flash_chip_operate.c //与上层接口函数：EE_RD_data(unsigned int addr,unsigned char *p_data,unsigned char num) //**************************************************************************************** #include "Flash_chip.h" #include "inc/hw_types.h" #include "inc/hw_memmap.h" #include "driverlib/gpio.h" #include "driverlib/debug.h" #include "driverlib/ssi.h" //**************************************************************************************** #define WREN 0x06 //允许写操作 #define WRDI 0x04 //禁止写操作 #define RDSR 0x05 //读状态寄存器 #define WRSR 0x01 //写状态寄存器 #define READ 0x0B //读数据 #define WRITE 0x02 //写数据 #define EE_SPI_CS_SET GPIOPinWrite(GPIO_PORTA_BASE , GPIO_PIN_3 , 0xFF) #define EE_SPI_CS_CLR GPIOPinWrite(GPIO_PORTA_BASE , GPIO_PIN_3 , 0x00) //************************************************************************************ void spi1_init(void) { unsigned long temp2[8]; SysCtlPeripheralEnable(SYSCTL_PERIPH_SSI0); //Enable SSIO SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA); //Enable GPIOA //GPIOPinConfigure(GPIO_PE1_SSI1FSS); GPIOPinConfigure(GPIO_PA2_SSI0CLK); //Configure PA2 as SSI CLK function GPIOPinConfigure(GPIO_PA4_SSI0RX); //Configure PA4 as SSI RX function GPIOPinConfigure(GPIO_PA5_SSI0TX); //Configure PA5 as SSI TX function GPIOPinTypeSSI(GPIO_PORTA_BASE, GPIO_PIN_2 | GPIO_PIN_4 |GPIO_PIN_5); //GPIO_PIN_1 | //Configure Pin() as SSI function SSIConfigSetExpClk(SSI0_BASE, SysCtlClockGet(), SSI_FRF_MOTO_MODE_0,SSI_MODE_MASTER, 10000000, 8); //Configure the SSI interface SSIEnable(SSI0_BASE); //Enable the SSI function GPIOPinTypeGPIOOutput(GPIO_PORTA_BASE , GPIO_PIN_3); //Configyre GPIOA3 as output ,using for control the CE of the external memory GPIOPadConfigSet(GPIO_PORTA_BASE,GPIO_PIN_3,GPIO_STRENGTH_2MA,GPIO_PIN_TYPE_STD); //Configure GPIOA3 as 推挽，2mA EE_SPI_CS_SET; //PA3 High level while(SSIDataGetNonBlocking(SSI0_BASE, &temp2[0])) //get data from the ssi,save at temp2 { } } //************************************************************************************ void Send_Byte(unsigned char data) { unsigned long NullData; SSIDataPut(SSI0_BASE, data); SSIDataGet(SSI0_BASE, &NullData); } //************************************************************************************* unsigned char Get_Byte(void) { unsigned long ReadData; SSIDataPut(SSI0_BASE, 0xFF); //发送一个无效字节，以产生接收时钟 SSIDataGet(SSI0_BASE, &ReadData); return (unsigned char)ReadData; } void EE_RD_data(unsigned int addr,unsigned char *p_data,unsigned char num) { #define SSI_O_SR 0xc #define SSI_SR_RNE 0x4 #define SSI_O_DR 0x8 #define SSI_SR_TNF 0x02 unsigned char i;//,addr_h,addr_m,addr_l; register unsigned long ReadAddress=SSI0_BASE+SSI_O_DR; EE_SPI_CS_CLR; Send_Byte(READ); Send_Byte(addr>>16); Send_Byte(addr>>8); Send_Byte(addr); Send_Byte(0xFF); //50M速度时用 __nop(); for(i=0;i<num;i++) { //*(p_data+i) = Get_Byte(); //以下三句话相当与这一句话，但是要比这句话快 HWREG(ReadAddress) = 0xff; while(!(HWREG(SSI0_BASE+SSI_O_SR)&SSI_SR_RNE)){} *(p_data+i) = (unsigned char )HWREG(ReadAddress); } __nop(); EE_SPI_CS_SET; } //************************************************************************************* /* void EE_RD_data(unsigned int addr,unsigned char *p_data,unsigned char num) //time=time1*5 +time2=76.16us { unsigned char i,addr_h,addr_m,addr_l; EE_SPI_CS_CLR; addr_l=addr; addr_m=addr>>8; addr_h=addr>>16; Send_Byte(READ); //1M:9.88us ,(time1=9.22+0.3=9.52us) //2M:5.2us Send_Byte(addr_h); Send_Byte(addr_m); Send_Byte(addr_l); Send_Byte(0xFF); //50M速度时用 __nop(); for(i=0;i<num;i++) //time2=3*9.52=28.56us { } __nop(); EE_SPI_CS_SET; } */