Develop custom board with STM32H747BIT6

[AlfredoFiori]

Good afternoon,

I am developing an hardware with microcontroller in Object.

I'm using the LQFP208 package because in my opinion it's easier to solder/remove in my lab.

For my application I need the support for:

• ETHERNET
• FMC for SDRAM
• QUADSPI
• SDMMC1
• USB OTG FS
• LTDC
• UART, I2C and SPI

when I try to create the IOC file I have some problems with the FMC setting for the SDRAM.

All the peripherals end with the green check instead I have a warning on the FMC and so I don't understand whether or not I can use this processor with these requirements.

Anyone could help me?

Thanks in advance

Alfredo

[SofLit]

Hello,

Normally you can use this device for this list of peripherals. What is the warning showing on the FMC? is it something related to shared GPIOs between the peripherals you're using (conflicting IOs)? If it's the case you need to juggle with the IOs selection to fit your application requirements.

[Tesla DeLorean]

There's also Data Sheets and Pencils,

SDRAM with large bus widths will eat pins

RGB via LTDC can eat upward of 16 or 24 pins, plus a couple of control pins.

[AlfredoFiori]

Good morning,

thanks for your soon reply! 

I recently started working with the STM32 and I'm reading a lot of datasheets. Many times it's not exactly easy to change microcontroller.

It is the first time I develop a board with STM32 microcontroller.

My design it is based on MB1381 Board.

I try to explain better what I see.

At the moment these are the peripherals I try to enable. Beside this LTDC controller too.

I click each one peripherals and enable with following parameter:

• MII: Full Duplex Only
• QUADSPI: Bank1 with single/dual Lines
• SDMMC1: SD 1 Bit
• USB_OTG_FS: 

Then I see the pins correctly mapped on Microcontroller.

Subsequently I try to enable:

• LTDC: RGB888 24Bit - DSI Mode

The peripherals is checked green but the pins are not automatically configurated.

Why the application does not default pins mapping?

I have to load each pin one by one?

For now I left without LTDC pins not configurated.

Then I try to configurate the FMC.

I enable the SDRAM1 with the parameters in picture.

Instantly some peripherals report a warning.

The default pins for FMC are mapped.

Following the warning I read

At this point I change Ethernet to RMII

The warning disappared but in FMC remain.

Partly disabled conflict with:

what exactly does it mean?

Thanks in advance 

Alfredo

[SofLit]

Hello,

Thank your for the sharing.

Is that possible to share your ioc file?

[AlfredoFiori]

Here it is!

Alfredo

[SofLit]

Indeed you have a GPIO conflict on PC5: FMC_SDCKE0 with ETH_RMII_RXD1 

and also on PC4: FMC_SDNE0 with ETH_RMII_RXD0 

So Select SDCKE1+SDNE1 (to use BANK2) instead of SDCKE0+SDNE0 (BANK1)

[AlfredoFiori]

Using SDCKE0+SDNE0 the port mapping are:

• FMC_SDCKE0 on Pin PC3C
• FMC_SDNE0 on Pin PC2C

On this pins there are not Ethernet connections.

In any case using SDCKE1+SDNE1 the port mapping are:

• FMC_SDCKE1 on Pin PH7
• FMC_SDNE1 on Pin PH6

On this pins there are not Ethernet connections

The problem remains...

[SofLit · Accepted solution]

No, The warning is not the same.

In the first warning: it points out a conflict between ETH and SDRAM but in the second one it's showing a conflict between two SDRAM banks which is from point of view not correct. Moreover the second SDRAM is not enabled so no reason to show a warning on something that was disabled.

So you can use Bank2 for SDRAM in your case.

I've already raised the behavior of CubeMx on ticket number 172341.

[AlfredoFiori]

Ok.

I put SDCKE1+SDNE1.

In any way:

Regards LTDC my previous Questions was:

Why the application does not default pins mapping?

I have to load each pin one by one?

Thanks

Alfredo