How to handle DCMI and LTDC pin conflicts on STM32F429I-Discovery

[chachamaru]

Hello,
I’m using an STM32F429I-Discovery board with an MT9M001 camera module, trying to display the camera image on the board’s built-in LCD.

However, I found that the following pins conflict between the DCMI and LTDC functions (please correct me if I misread the pin mapping):

• PA4: DCMI_HSYNC vs LTDC_VSYNC

• PA6: DCMI_PIXCLK vs LTDC_G2

• PC7: DCMI_D1 vs LTDC_G6

• PB8: I2C1_SCL vs LTDC_B6

• PB9: I2C1_SDA vs LTDC_B7

In this situation, what is the typical way to handle such pin conflicts?
Would it be necessary to change the board or the camera module?

Any advice would be greatly appreciated.
Thank you in advance.

[Ghofrane GSOURI]

Hello @chachamaru 

After reviewing the STM32F429 datasheet (DS9405 Rev 12), it is clear that on the STM32F429I-Discovery board (LQFP144 package), there are unavoidable pin conflicts between the DCMI (camera interface) and LTDC (LCD controller) peripherals. These conflicts arise from fixed pin assignments that cannot be remapped, making it impossible to use both peripherals simultaneously. Typical solutions include using only one peripheral at a time , switching to a different board with a more compatible pinout, or selecting a camera module that uses a different interface, such as SPI or I2C, to avoid these conflicts.

THX

Ghofrane