DCMI+LTDC+USB - Why Not Possible

[MHenz]

I am very intrigued by the new STM32H7A and STM32H7B value line microcontrollers. I think these will be a great success for ST. However, I am dissapointed to discover that I cannot configure an STM32H7A3ZIT in an LQFP144 package to use a camera, a display and a USB port simultaneously. It seems like a natural combination. However, if I enable the DCMI and LTDC interface together . . . then the USB interface is no longer available. Seems like a big oversight to me. Any workarounds for this?

Thanks for your help,

Max

[berendi]

Using the LCD interface in 15 bit mode RGB555 mode allows mapping LTDC_R5 to PC0 instead of LDTC_G2, freeing up PA12 for USB HS.

The difference between RGB555 and RGB565 is that LTDC_G2 is not used, otherwise configure it exactly as RGB565.

[MHenz]

Thank you for this suggestion . . . I really appreciate your help. I will give it a try.

[MHenz]

I appreciate your suggestion, but I cannot figure out how to setup RGB555 mode. This mode is not available in STM32CubeIDE. If I select RGB565 mode and then try to reassign LTDC_R5 to PC0, then all of the pins previously mapped to LTDC functions disappear and the LTDC interface is disabled. How do I set up RGB555 mode? Thank you.

[berendi]

STM32CubeIDE can't do it, set the GPIO MODER/AFR registers by software.

See the GPIO register descriptions in the reference manual, and get the values that go in the AFR register fields from the Alternate function mapping table in the datasheet.

[MHenz]

Thank you again for your help.

I will try this.

All the best,

Max