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I am configuring a new LCD screen with parallel 8080 protocol (screen controller is SSD1351). I am using ST CubeMX to generate code for FMC (attached picture of the configuration).

My problem is that when I try to write a command, my D0-D7 are always 0 and D/C, WR and RD are behaving weirdly. I think it is related with some configuration or incorrect way to send the command.

ST CubeMX configuration:

STM CubeMX configuration screenshot

FMC init code:

/* FMC initialization function */
static void MX_FMC_Init(void)
{
  FMC_NORSRAM_TimingTypeDef Timing;

  /** 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_8;
  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_DISABLE;
  hsram1.Init.PageSize = FMC_PAGE_SIZE_NONE;
  /* Timing */
  Timing.AddressSetupTime = 2;
  Timing.AddressHoldTime = 0;
  Timing.DataSetupTime = 4;
  Timing.BusTurnAroundDuration = 0;
  Timing.CLKDivision = 0;
  Timing.DataLatency = 0;
  Timing.AccessMode = FMC_ACCESS_MODE_A;
  /* ExtTiming */

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

}

Because I use bank1 the address to write is 0x60000000

#define  LCD_BASE_Addr                  ((uint32_t * )(0x60000000))
#define  LCD_BASE_Data               ((uint32_t *)(0x60000000|0x00000001))

My write command is:

void LCD_SendCommand(uint8_t  com){
    *(__IO uint32_t*)(LCD_BASE_Addr) = com;
}

Command example call:

LCD_SendCommand(0xAF);

Oscilloscope output:

Oscilloscope screenshot

Small guide for scope configuration: On the left side there are signal names, but they are not D0-D7 data signals.

  • D1 - is CS
  • D2 - is D/C
  • D3 - is WR
  • D4 - is RD
  • D5 - is D0 (data)

My questions:

  1. Why it is generating 16 commands (16 times D/C)?
  2. Is my write command correct?
  3. Where are D0-D7 configured? In the CubeMX I save the D0-D7 configured as Data pins but not on FMC init.

Thanks for your help.

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The problem was the incorrect controller package. The signal really shown as some CLK and it was really weird for me. After checking the package those pins were also CLK pins.

Thanks!

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