SM32L4 interface with an eMMC

[Lukasz Przenioslo]

Posted on May 09, 2018 at 13:10

Hello there,

I am using STM32L452. I would like to interface with a SanDisk eMMC memory (

SDINBDG4-8G-XI1

).

In cubeMX, when I configure the project and choose SDMMC1->MMC 4 bits Wide bus, I get the following:

Does that mean that there is no ready HAL functions? Or, for instance, can I use the SD 4 bits Wide bus for communication? Are those interfaces compatible in STM32?

I would appreciate all help.

#sd-card- #emmc #mmc

[Tesla DeLorean]

Posted on May 09, 2018 at 14:09

Which part specifically?

Not available on 48 pin devices, or some 64-pin ones

http://www.st.com/content/ccc/resource/technical/document/datasheet/group3/fc/c2/8d/b7/99/d8/42/9e/DM00340549/files/DM00340549.pdf/jcr:content/translations/en.DM00340549.pdf

 

[Lukasz Przenioslo]

Posted on May 09, 2018 at 14:33

In the end will need to do that probably. But with having no examples for configuration the task is harder. Do you know either there are any eMMC BSP for other STM32 family MCU's? Also, will this be supported in cubeMX for L4 in future?

DAHMEN.IMEN

‌ ?

Also there is one thing not clear to me: For the L4 package i could find only the low layer MMC library, while F4 and F7 have HAL library. Are they compatible, or can I not use the HAL one for L4 device? This is additionally unclear, since in the cubeMX project options I cannot choose LL for eMMC but only HAL, which is not there...

[Lukasz Przenioslo]

Posted on May 09, 2018 at 14:15

The hardware is there, the parts I am trying to use it for are:

STM32L452VETx

STM32L452RETx

No external SMPS there.

[Tesla DeLorean]

Posted on May 09, 2018 at 14:25

Well it could be a CubeMX 'Computer Says No' moment, I'd just use the HAL

Make sure you have the PLL enabled, not sure if that part allows routing of SYSCLK into the SDMMC

[Tesla DeLorean]

Posted on May 09, 2018 at 14:59

The whole SDIO/SDMMC and HAL/LL across the families is a bit quixotic, it might get more unified over time. My concerns tend to be whether things work or not, and keep my top-level code portable

I take this approach to finding the appropriate base example in HAL/LL/SPL, and hack it into shape, then merge in my functionality

https://www.youtube.com/watch?v=SkvY7HuaapE

 

[Lukasz Przenioslo]

Posted on May 09, 2018 at 15:02

I get the point. But I would just like to know on what I am standing in this eMMC situation- make sure the lib exists or not, but can be copied from F4 for example, because its the same. Also I had no idea there is so much overhead in making the coconut look the way it does after its taken from the tree.

[Imen.D]

Posted on May 09, 2018 at 15:05

Hello

Przenioslo.Lukasz

I forward your questions to the appropriate team to clarify your case.

Best Regards,

Imen

[Lukasz Przenioslo]

Posted on May 09, 2018 at 15:07

Thank you,

I have just created the cubeMX project and imported it to truestudio. The SDMMC1 init function generated is empty:

/* SDMMC1 init function */void MX_SDMMC1_Init(void){}

It doesnt even consist of USER CODE BEGIN and END statemens to its not really usable.

[Tesla DeLorean]

Posted on May 09, 2018 at 15:50

I'm surprised the guy seems to have all his fingers...