void spi_transfer(unsigned char *Data_in, unsigned char *Data_out, int DataLen, GPIO_PinTypeDef CSPin)
{
gpio_write(CSPin,0); //CS level is low
reg_spi_ctrl &= ~FLD_SPI_DATA_OUT_DIS; ////0x09- bit2 enables spi data output
reg_spi_ctrl &= ~FLD_SPI_RD; //enable write,0x09-bit3 : 0 for...