Error while configuring STM32H747BIT6 with SDRAM IS42S16320D(SDRAM IC).

[Rushali]

When ever i am trying to copy data in SDRAM garbage value is getting transferred. Please suggest what can i do

I have attached necessary files with this post.

Kindly suggest.

[KDJEM.1]

Hello @Rushali and welcome to the Community 🙂,

Please make sure that the timing parameters are set correctly.

I think that How to set up the FMC peripheral to interface with the SDRAM IS42S16800F-6BLI from ISSI FAQ  can help you.

Also, you can start by an available example such as FMC_SDRAM_DataMemory and get inspired to configure your project.

Note that, this example has been tested with STM32H747I-EVAL board with SMPS (SD Converter) power supply config when the SDRAM is IS42S32800G, but can be easily tailored to any other supported device and development board.

I hope this help you!

Kaouthar

[Rushali]

Thank you for your reply.But i have narrowed down the problem.i found out that while initalizing SDRAM with FMC i have written following code.

void FMC_INIT(void) {

HAL_StatusTypeDef status;

/* Step 1 and Step 2 already done in HAL_SDRAM_Init() */

/* Step 3: Configure a clock configuration enable command */

Command.CommandMode = FMC_SDRAM_CMD_CLK_ENABLE; /* Set MODE bits to "001" */

Command.CommandTarget = FMC_SDRAM_CMD_TARGET_BANK2 ; /* configure the Target Bank bits */

Command.AutoRefreshNumber = 3;

Command.ModeRegisterDefinition = 0;

/* while (FMC_GetFlagStatus(FMC_Bank2_SDRAM, FMC_FLAG_Busy) != RESET) {

}*/

/* Send the command */

status = HAL_SDRAM_SendCommand(&hsdram1, &Command, 0xfff);

HAL_Delay(1); /* Step 4: Insert 100 us minimum delay - Min HAL Delay is 1ms */

/* Step 5: Configure a PALL (precharge all) command */

Command.CommandMode = FMC_SDRAM_CMD_PALL; /* Set MODE bits to "010" */

HAL_SDRAM_SendCommand(&hsdram1, &Command, 0xfff);

/* Step 6: Configure an Auto Refresh command */

Command.CommandMode = FMC_SDRAM_CMD_AUTOREFRESH_MODE; /* Set MODE bits to "011" */

Command.AutoRefreshNumber = 2;

HAL_SDRAM_SendCommand(&hsdram1, &Command, 0xfff);

/* Step 7: Program the external memory mode register */

Command.CommandMode = FMC_SDRAM_CMD_LOAD_MODE;/*set the MODE bits to "100" */

Command.ModeRegisterDefinition = (uint32_t)0 | 0<<3 | 2<<4 | 0<<7 | 1<<9;

HAL_SDRAM_SendCommand(&hsdram1, &Command, 0xfff);

/* Step 8: Set the refresh rate counter - refer to section SDRAM refresh timer register in RM0455 */

/* Set the device refresh rate

* COUNT = [(SDRAM self refresh time / number of row) x SDRAM CLK] – 20

= [(64ms/4096) * 100MHz] - 20 = 1562.5 - 20 ~ 1542 */

HAL_SDRAM_ProgramRefreshRate(&hsdram1, 733);

}

But unable to change command mode value after sending commands.

[KDJEM.1 · Accepted solution]

Hello @Rushali ,

--> unable to change command mode value after sending commands.

Thank you for bringing this issue to our attention.

After checking, I confirm that the MODE Bits read as zero after the command is issued and this is normal behavior.

The MODE bits are write only. For that I reported the reference manual internally for correction.

Internal ticket number: 169917 (This is an internal tracking number and is not accessible or usable by customers).

Thank you.

Kaouthar