FMC Writing to all Subsequent Memory Addresses

[user20324-245]

Hello,

I am trying to use FMC on an STM32U5G9J-DK2 to communicate with an LCD (ST7789). I am trying to send initialization commands to the device as follows

define FMC_BANK1_REG ((volatile uint16_t *)0x60000000)
#define FMC_BANK1_DATA ((volatile uint16_t *)0x60000002)

void write_command(uint8_t data)
{
  volatile uint16_t *p = FMC_BANK1_REG;
  *p = (uint16_t)(data);
}

void write_data(uint16_t data)
{
  volatile uint16_t *p = FMC_BANK1_DATA;
  *p = data;
}

// Ex:
write_command(0xFF)

However, when I write 0xFF to memory at address 0x60000000, I don't just see the value written to the single memory address. Instead, it appears to be writing to many subsequent memory addresses. What I see is FF00FF00 written to all addresses between 0x60000000 and 0x600001CC. I understand that the memory is little endian, so FF00 is expected. However, I am unsure why it is repeating to other addresses. I am using the default, CubeMX generated code for FMC initialization, shown below.

/* FMC initialization function */
static void MX_FMC_Init(void)
{

  /* USER CODE BEGIN FMC_Init 0 */

  /* USER CODE END FMC_Init 0 */

  FMC_NORSRAM_TimingTypeDef Timing = {0};

  /* USER CODE BEGIN FMC_Init 1 */

  /* USER CODE END FMC_Init 1 */

  /** Perform the SRAM1 memory initialization sequence
   */
  hsram1.Instance = FMC_NORSRAM_DEVICE;
  hsram1.Extended = FMC_NORSRAM_EXTENDED_DEVICE;
  /* hsram1.Init */
  hsram1.Init.NSBank = FMC_NORSRAM_BANK1;
  hsram1.Init.DataAddressMux = FMC_DATA_ADDRESS_MUX_DISABLE;
  hsram1.Init.MemoryType = FMC_MEMORY_TYPE_SRAM;
  hsram1.Init.MemoryDataWidth = FMC_NORSRAM_MEM_BUS_WIDTH_16;
  hsram1.Init.BurstAccessMode = FMC_BURST_ACCESS_MODE_DISABLE;
  hsram1.Init.WaitSignalPolarity = FMC_WAIT_SIGNAL_POLARITY_LOW;
  hsram1.Init.WaitSignalActive = FMC_WAIT_TIMING_BEFORE_WS;
  hsram1.Init.WriteOperation = FMC_WRITE_OPERATION_ENABLE;
  hsram1.Init.WaitSignal = FMC_WAIT_SIGNAL_DISABLE;
  hsram1.Init.ExtendedMode = FMC_EXTENDED_MODE_DISABLE;
  hsram1.Init.AsynchronousWait = FMC_ASYNCHRONOUS_WAIT_DISABLE;
  hsram1.Init.WriteBurst = FMC_WRITE_BURST_DISABLE;
  hsram1.Init.ContinuousClock = FMC_CONTINUOUS_CLOCK_SYNC_ONLY;
  hsram1.Init.WriteFifo = FMC_WRITE_FIFO_ENABLE;
  hsram1.Init.NBLSetupTime = 0;
  hsram1.Init.PageSize = FMC_PAGE_SIZE_NONE;
  hsram1.Init.MaxChipSelectPulse = DISABLE;
  /* Timing */
  Timing.AddressSetupTime = 3;
  Timing.AddressHoldTime = 15;
  Timing.DataSetupTime = 2;
  Timing.DataHoldTime = 2;
  Timing.BusTurnAroundDuration = 2;
  Timing.CLKDivision = 16;
  Timing.DataLatency = 17;
  Timing.AccessMode = FMC_ACCESS_MODE_A;
  /* ExtTiming */

  if (HAL_SRAM_Init(&hsram1, &Timing, NULL) != HAL_OK)
  {
    Error_Handler();
  }

  /* USER CODE BEGIN FMC_Init 2 */

  /* USER CODE END FMC_Init 2 */
}

If anyone could provide help on this matter, it would be greatly appreciated.