MCP23S17 an STM32F4 Problem

void init_SPI1(void){

  GPIO_InitTypeDef GPIO_InitStruct;

  SPI_InitTypeDef SPI_InitStruct;

  // enable clock for used IO pins

  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);

  /* configure pins used by SPI1

   * PA5 = SCK

   * PA6 = MISO

   * PA7 = MOSI

   */

  GPIO_InitStruct.GPIO_Pin = GPIO_Pin_7 | GPIO_Pin_6 | GPIO_Pin_5;

  GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;

  GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;

  GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;

  GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_NOPULL;

  GPIO_Init(GPIOA, &GPIO_InitStruct);

  // connect SPI1 pins to SPI alternate function

  GPIO_PinAFConfig(GPIOA, GPIO_PinSource5, GPIO_AF_SPI1);

  GPIO_PinAFConfig(GPIOA, GPIO_PinSource6, GPIO_AF_SPI1);

  GPIO_PinAFConfig(GPIOA, GPIO_PinSource7, GPIO_AF_SPI1);

  // enable clock for used IO pins

  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE, ENABLE);

  /* Configure the chip select pin

     in this case we will use PE7 */

  GPIO_InitStruct.GPIO_Pin = GPIO_Pin_7;

  GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;

  GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;

  GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;

  GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_UP;

  GPIO_Init(GPIOE, &GPIO_InitStruct);

  GPIOE->BSRRL |= GPIO_Pin_7; // set PE7 high

  // enable peripheral clock

  RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);

  /* configure SPI1 in Mode 0

   * CPOL = 0 --> clock is low when idle

   * CPHA = 0 --> data is sampled at the first edge

   */

  //SPI_InitStruct.SPI_Direction = SPI_Direction_2Lines_FullDuplex; // set to full duplex mode, seperate MOSI and MISO lines

  SPI_InitStruct.SPI_Direction = SPI_Direction_1Line_Tx;

  SPI_InitStruct.SPI_Mode = SPI_Mode_Master;     // transmit in master mode, NSS pin has to be always high

  SPI_InitStruct.SPI_DataSize = SPI_DataSize_8b; // one packet of data is 8 bits wide

  SPI_InitStruct.SPI_CPOL = SPI_CPOL_Low;        // clock is low when idle

  SPI_InitStruct.SPI_CPHA = SPI_CPHA_1Edge;      // data sampled at first edge

  SPI_InitStruct.SPI_NSS = SPI_NSS_Soft; // set the NSS management to internal and pull internal NSS high

  SPI_InitStruct.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_256; // SPI frequency

  SPI_InitStruct.SPI_FirstBit = SPI_FirstBit_MSB;// data is transmitted MSB first

  SPI_Init(SPI1, &SPI_InitStruct);

  SPI_Cmd(SPI1, ENABLE); // enable SPI1

}

void spi_setup(){

  Delay(10000000L);

  GPIOE->BSRRH |= GPIO_Pin_7; // set PE7 (CS) low

  SPI_Xfer(0x40);

  SPI_Xfer(0x0A);        // IOCON

  test=SPI_Xfer(0xB8);

  GPIOE->BSRRL |= GPIO_Pin_7; // set PE7 (CS) high

  Delay(1000);

  GPIOE->BSRRH |= GPIO_Pin_7; // set PE7 (CS) low

  SPI_Xfer(0x40);

  SPI_Xfer(0x00);        //IODIRA

  test=SPI_Xfer(0x00);

  GPIOE->BSRRL |= GPIO_Pin_7; // set PE7 (CS) high

  Delay(1000);

  GPIOE->BSRRH |= GPIO_Pin_7; // set PE7 (CS) low

  SPI_Xfer(0x40);

  SPI_Xfer(0x10);        //IODIRB

  test=SPI_Xfer(0x00);

  GPIOE->BSRRL |= GPIO_Pin_7; // set PE7 (CS) high

}

uint8_t SPI_Xfer(uint8_t data){

    /*!< Loop while DR register in not emplty */

    while (SPI_I2S_GetFlagStatus(SPI1, SPI_I2S_FLAG_TXE) == RESET);

      SPI_I2S_SendData(SPI1,data);

    return data;

    //return SPI1->DR;

}

    GPIOE->BSRRH |= GPIO_Pin_7; // set PE7 (CS) low

    SPI_Xfer(0x40);  //Device Optcode

    SPI_Xfer(0x0A);  // OLATA, Adress

    test=SPI_Xfer(0xFF);  // Daten

    GPIOE->BSRRL |= GPIO_Pin_7; // set PE7 (CS) high

                LD_4_EIN;  //Test LED

    Delay(100000000L);

    GPIOE->BSRRH |= GPIO_Pin_7; // set PE7 (CS) low

    SPI_Xfer(0x40);  //Device Optcode

    SPI_Xfer(0x0A);  // OLATA, Adress

    test=SPI_Xfer(0x00);  // Daten

    GPIOE->BSRRL |= GPIO_Pin_7; // set PE7 (CS) high

    LD_4_AUS;  //Test LED

    Delay(100000000L);