Have to choose between STM32H7B3 and STM32F7xx

[PSEBA.1]

Hello all,

I have to develop an application with a 7 inch screen driver SSD1963,
for the choice of cpu. I'm deciding between an STM32H7B3 and STM32F7xx, on the card I need RAM for screen storage,
touchscreen management, communication with an FPGA in SPI and good fluidity when changing screens. Do you have any advice for choosing the CPU?
Best regards,

Sébastien

[mƎALLEm]

Hello,

That depends on your application and how you will use the product including performance and power consumption.

Of course STM32H7B3 running up to 280Mhz (599 DMIPS/ 2.14 DMIPS/MHz) is more performant than STM32F7 running up to 216MHz (462 DMIPS/2.14 DMIPS/MHz (Dhrystone 2.1)). with more internal RAM resources than F7 family.

But you need to refer to the datasheet of each product to have an idea which one fits to your application in term of resources: Internal RAM, Flash, features, etc ..

https://www.st.com/resource/en/datasheet/stm32h7b3ri.pdf

https://www.st.com/resource/en/datasheet/stm32f765bi.pdf

You need also to think about the price ..

 

[LCE]

I'd go for the H7, because of more external RAM options.

The F7 has only the FMC option, which makes PCB layout much harder and takes many GPIOs.

The H7 (at least H733, H735) works well with HyperRAM via its OCTOSPI peripheral in memory-mapped mode.

And can't say much about graphics stuff, but at least the H7 has a higher CPU clock rate.

[PSEBA.1]

thank you for your answer,
I want to use the ssd1963 driver in 16-bit mode with an 800x480 screen,
I wanted to take the MB1331 development card (STM32H7B3LI) as a reference
and modify the diagram to adapt it to my application.
I have a lot of screen to store and I want to have a smooth display
Best regards.
Sébastien.

[mƎALLEm]

You need to use FMC interface to drive ssd1963 LCD driver:

MB1331 (STM32H7B3I-EVAL) has only external RAM via FMC (SDRAM+PSRAM). So there will be some contention on FMC interface if you will drive the LCD on it. Hard to tell you if the display will be smooth or not. You need to run your tests and check. If you noticed some issues I recommend to use HyperRAM over OSPI interface and LCD on FMC.