STM32f746 board[LTDC and I2C ] vs CUSTOM board[only LTDC] pin connection with LCD Display

[Uc.2361]

Hello Touchgfx Team,

In STM32f746 disc board there is LTDC as well as I2C peripherals used for the LCD

Where as the custom board which I am using has only LTDC and there is no I2C peripheral connected to the LCD display.

Why does the I2C peripheral used in discovery board , is that used for controlling touch on the Display.

If so the Custom board which I have will it work by using only LTDC peripheral.

All LCD related features will they work with LTDC alone or need I2C as well?

Please let me know.

Thanks,

Upender.

[berendi]

This depends on the display model, some require some configuring/register setting through I2C or SPI at startup to function, some don't.

Refer to the LCD panel datasheet and the LCD controller datasheet, both should be available from the manufacturer or distributor.

[HP]

if you look at the datasheet you'll see that the I2C connection is for the touchscreen interface.

The F746 is using a capacitive digitizer running over I2C. The display itself is 'only' parallel 24-bit RGB data with clock and sync lines. so that works fine with the LTDC interface.

[Uc.2361]

Thank you for the quick response.

Yes you both are right,

I have checked the application note of the ST's LTDC. and even Datasheet of the LCD.

It is mentioned,

LTDC is 24-bit RGB data with clock, hsync, vsync for Displaying Data.

I2C is for CTP[capacitive touch panels] is for touch.

Summary: My custom board doesnot work for Touch, It should be used only Displaying the content.

Thanks,

Upender.