SPI_InitTypeDef SPI_InitStruct;
GPIO_InitTypeDef GPIO_InitStruct;
// Step 2: Initialize GPIO
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
// GPIO pins for MOSI, MISO, and SCK
GPIO_InitStruct.GPIO_Pin = SPI_MASTER_PIN_MOSI | SPI_MASTER_PIN_MISO |
SPI_MASTER_PIN_SCK;
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_Init(SPI_MASTER_GPIO, &GPIO_InitStruct);
// GPIO pin for SS
GPIO_InitStruct.GPIO_Pin = GPIO_Pin_12;
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_Init(SPI_MASTER_GPIO, &GPIO_InitStruct);
      SPI_MASTER_GPIO->BRR =GPIO_Pin_12;
// Step 1: Initialize SPI
RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI2, ENABLE);
SPI_InitStruct.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_128;
SPI_InitStruct.SPI_CPHA = SPI_CPHA_1Edge;
SPI_InitStruct.SPI_CPOL = SPI_CPOL_Low;
SPI_InitStruct.SPI_DataSize = SPI_DataSize_8b;
SPI_InitStruct.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
SPI_InitStruct.SPI_FirstBit = SPI_FirstBit_MSB;
SPI_InitStruct.SPI_Mode = SPI_Mode_Master;
SPI_InitStruct.SPI_NSS = SPI_NSS_Soft | SPI_NSSInternalSoft_Set;
SPI_Init(SPI_MASTER  , &SPI_InitStruct);
SPI_Cmd(SPI_MASTER , ENABLE);