CCS: 28335 McBSP used as SPI,receive data is always 0xFF

void  Mcbsp_gpio_init(void)
{

    EALLOW;
/* Configure McBSP-A pins using GPIO regs*/
// This specifies which of the possible GPIO pins will be McBSP functional pins.
// Comment out other unwanted lines.
 GpioCtrlRegs.GPAMUX2.bit.GPIO24 = 3; // GPIO24 is MDXB pin (Comment as needed)
 GpioCtrlRegs.GPAMUX2.bit.GPIO25 = 3; // GPIO25 is MDRB pin (Comment as needed)
 GpioCtrlRegs.GPAMUX2.bit.GPIO26 = 3; // GPIO26 is MCLKXB pin (Comment as needed)
// GpioCtrlRegs.GPAMUX2.bit.GPIO27 = 3; // GPIO27 is MFSXB pin (Comment as needed)
/* Enable internal pull-up for the selected pins */
// Pull-ups can be enabled or disabled by the user.
// This will enable the pullups for the specified pins.
// Comment out other unwanted lines.
 GpioCtrlRegs.GPAPUD.bit.GPIO24 = 0;     // Enable pull-up on GPIO24 (MDXB) (Comment as needed)
 GpioCtrlRegs.GPAPUD.bit.GPIO25 = 0;     // Enable pull-up on GPIO25 (MDRB) (Comment as needed)
 GpioCtrlRegs.GPAPUD.bit.GPIO26 = 0;     // Enable pull-up on GPIO26 (MCLKXB) (Comment as needed)
// GpioCtrlRegs.GPAPUD.bit.GPIO27 = 0;     // Enable pull-up on GPIO27 (MFSXB) (Comment as needed)

/* Set qualification for selected input pins to asynch only */
// This will select asynch (no qualification) for the selected pins.
// Comment out other unwanted lines.
    GpioCtrlRegs.GPAQSEL2.bit.GPIO25 = 3;   // Asynch input GPIO25 (MDRB) (Comment as needed)
    GpioCtrlRegs.GPAQSEL2.bit.GPIO26 = 3;   // Asynch input GPIO26(MCLKXB) (Comment as needed)
//    GpioCtrlRegs.GPAQSEL2.bit.GPIO27 = 3;   // Asynch input GPIO27 (MFSXB) (Comment as needed)
 EDIS;
}

void Mcbsp_ModelFun_init(struct MCBSP_REGS *pMcbspReg )
{
 //step1 reset tx rx Place the transmitter and receiver in reset.
  pMcbspReg->SPCR2.bit.XRST = 0;
  pMcbspReg->SPCR1.bit.RRST = 0;
  //step2  Place the sample rate generator in reset
  pMcbspReg->SPCR2.bit.GRST = 0;
  pMcbspReg->SPCR2.bit.FRST = 0;

  pMcbspReg->PCR.all=0x0F08;  //(CLKXM=CLKRM=FSXM=FSRM= 1, FSXP = 1)

  pMcbspReg->SPCR1.bit.DLB =0;//0: not loopback mode,1:loopback mode
  //step3 Program registers that affect SPI operation
  pMcbspReg->SPCR1.bit.CLKSTP = 2;//>=2 spimode

  pMcbspReg->PCR.bit.CLKXP =0;//bit1=0:Transmit data is sampled on the rising edge of CLKX.
  pMcbspReg->PCR.bit.CLKRP =0;//bit0:0:Receive data is sampled on the falling edge of MCLKR
//  pMcbspReg->PCR.bit.CLKXM =1;//master

  pMcbspReg->XCR2.bit.XPHASE = 0;//帧中只有一个阶段
  pMcbspReg->RCR2.bit.RPHASE = 0;//帧中只有一个阶段
  pMcbspReg->RCR2.bit.RDATDLY = 1;//master set 1
  pMcbspReg->XCR2.bit.XDATDLY = 1;//master set 1

  pMcbspReg->XCR1.all =0;//XFRLEN1=0,发送帧中只有一个字,XWDLEN1 =0,8bit per word
  pMcbspReg->RCR1.all =0;//RFRLEN1 =0,接收帧中只有一个字,RWDLEN1 =0,8bit per word
  //clk set
  pMcbspReg->PCR.bit.SCLKME =0;
  pMcbspReg->SRGR2.bit.CLKSM = 1;//LSPCLK
  pMcbspReg->SRGR1.bit.CLKGDV = 0xc7;// 0x4a:clkG=(150M/4)/(4A+1)=500Khz;0x7c clkG=(150M/4)/(7c+1)=300Khz;0xc7 :clkG=(150M/4)/(c7+1)=187.5Khz

//  pMcbspReg->XCR1.bit.XFRLEN1 = 0;//发送帧中只有一个字
//  pMcbspReg->RCR1.bit.RFRLEN1 = 0;//接收帧中只有一个字
//  pMcbspReg->XCR1.bit.XWDLEN1 = 0;//8bit per word
//  pMcbspReg->RCR1.bit.RWDLEN1 = 0;//8bit per word

  //step4 Enable the sample rate generator
  pMcbspReg->SPCR2.bit.GRST = 1;
  clkg_delay_loop();
  //step 5 Enable the transmitter and receiver
  pMcbspReg->SPCR1.bit.RRST = 1;
  pMcbspReg->SPCR2.bit.XRST = 1;
  pMcbspReg->SPCR2.bit.FRST = 1;
  clkg_delay_loop();
}

Ubyte SPI_WriteReadByte( Ubyte wri_data)
{

//    Ubyte reData = 0;
    McbspbRegs.DXR1.all = wri_data;
    while(McbspbRegs.SPCR1.bit.RRDY == 0){}
    return McbspbRegs.DRR1.all ;
//    reData = McbspbRegs.DRR1.all ;
 //   return reData;
}

#define FLASH_CS_H  Gpio_Write_TE(59, 1)
#define FLASH_CS_L  Gpio_Write_TE(59, 0)

uint16_t  Is25lp064_ReadREMS(void)
{
 uint16_t Temp = 0;
 FLASH_CS_L;
 Temp = SPI_WriteReadByte(0x90);
 Temp = SPI_WriteReadByte(0x00);
 Temp = SPI_WriteReadByte(0x00);
 Temp = SPI_WriteReadByte(0x00);

 Temp|=SPI_WriteReadByte(0xFF)<<8;    //Manufacturer ID =9dh
 Temp|=SPI_WriteReadByte(0xFF);  //Device ID ID =16h
 FLASH_CS_H;
 return Temp;
}

void Is25lp064_Init(void)
{
 Gpio_Set_Do_TE(59, TI_DO_PP);//flash_cs
 Gpio_Set_Do_TE(58, TI_DO_PP);//flash_wp
 Gpio_Set_Do_TE(63, TI_DO_PP);//flash_hold
 Gpio_Write_TE(58, 1);//0是写保护状态，1是不保护状态
 Gpio_Write_TE(63, 1);//拉低可以使设备处于暂停状态，恢复会高，设备继续拉低之前的工作 ,set 1不暂停
 FLASH_CS_H;//default not select
 Mcbsp_gpio_init();
}

#define MCP2515_CS_H  Gpio_Write_TE(27, 1)
#define MCP2515_CS_L  Gpio_Write_TE(27, 0)



Ubyte SPI_TX[20], SPI_RX[20];

void Mcp1515_Init(void)
{
 Gpio_Set_Do_TE(27, TI_DO_PP);//mcp2515_cs
 MCP2515_CS_H;//cs=1
 Gpio_Set_Di_TE(MCP2515_INT, TI_DI_NOPULL);//mcp2515_int
 Gpio_Set_Do_TE(50, TI_DO_PP);//mcp2515_reset
 Gpio_Write_TE(50, 0);//mcp2515_reset set 0 reset mode
// Sys_Delay(2);
 Gpio_Write_TE(50, 1);//
 /*MCp2515 和 Flash 共用 mcbsp接口    由于 Flash的初始化中调用了 Mcbsp_gpio_init  这里就不需要再次调用了。
  *
  *
  * */
}
void SPI_WR(Ubyte len)
{
    Ubyte i = 0;
    uint32_t Time_out = 0x1000;

    MCP2515_CS_L;//CS enable
    for(i=0; i<len; i++)
    {
        SPI_RX[i] = SPI_WriteReadByte(SPI_TX[i]);
    }

    MCP2515_CS_H; //cs Disable

}

int main()

{

//    //flash
  Is25lp064_Init();//flash gpio init
//  //mcp2515
  Mcp1515_Init();//mcp2515 gpio init
  Mcbsp_ModelFun_init(&McbspbRegs);

  while(1)
    {
     sdata1= Is25lp064_ReadREMS();

    }

}