#define REFRESH_COUNT       ((uint32_t)0x056A)   /* SDRAM refresh counter (90MHz SDRAM clock) */
#define SDRAM_BANK_ADDR     ((uint32_t)0xC0000000)
static void SDRAM_Initialization_Sequence(SDRAM_HandleTypeDef *hsdram, FMC_SDRAM_CommandTypeDef *Command)
{
  __IO uint32_t tmpmrd =0;
  /* Step 3:  Configure a clock configuration enable command */
  Command->CommandMode   = FMC_SDRAM_CMD_CLK_ENABLE;
  Command->CommandTarget   = FMC_SDRAM_CMD_TARGET_BANK1;
  Command->AutoRefreshNumber   = 1;
  Command->ModeRegisterDefinition = 0;
  /* Send the command */
  HAL_SDRAM_SendCommand(hsdram, Command, 0x1000);
  /* Step 4: Insert 100 ms delay */
  HAL_Delay(100);
  /* Step 5: Configure a PALL (precharge all) command */
  Command->CommandMode       = FMC_SDRAM_CMD_PALL;
  Command->CommandTarget        = FMC_SDRAM_CMD_TARGET_BANK1;
  Command->AutoRefreshNumber   = 1;
  Command->ModeRegisterDefinition = 0;
  /* Send the command */
  HAL_SDRAM_SendCommand(hsdram, Command, 0x1000);
  /* Step 6 : Configure a Auto-Refresh command */
  Command->CommandMode       = FMC_SDRAM_CMD_AUTOREFRESH_MODE;
  Command->CommandTarget     = FMC_SDRAM_CMD_TARGET_BANK1;
  Command->AutoRefreshNumber   = 4;
  Command->ModeRegisterDefinition = 0;
  /* Send the command */
  HAL_SDRAM_SendCommand(hsdram, Command, 0x1000);
  /* Step 7: Program the external memory mode register */
  tmpmrd = (uint32_t)SDRAM_MODEREG_BURST_LENGTH_2          |
                     SDRAM_MODEREG_BURST_TYPE_SEQUENTIAL   |
                     SDRAM_MODEREG_CAS_LATENCY_3           |
                     SDRAM_MODEREG_OPERATING_MODE_STANDARD |
                     SDRAM_MODEREG_WRITEBURST_MODE_SINGLE;
  Command->CommandMode = FMC_SDRAM_CMD_LOAD_MODE;
  Command->CommandTarget     = FMC_SDRAM_CMD_TARGET_BANK1;
  Command->AutoRefreshNumber   = 1;
  Command->ModeRegisterDefinition = tmpmrd;
  /* Send the command */
  HAL_SDRAM_SendCommand(hsdram, Command, 0x1000);
  /* Step 8: Set the refresh rate counter */
  /* (15.62 us x Freq) - 20 */
  /* Set the device refresh counter */
  HAL_SDRAM_ProgramRefreshRate(hsdram, REFRESH_COUNT);
}