MCUXpresso SDKのトピックRe: How to handle SD card eject & reinsert?

How to handle SD card eject & reinsert?

jackking — Sun, 02 Feb 2020 15:33:46 GMT

I am using the IMXRT1062 and testing the SDK examples for FatFS SDcard. It seems that when the card is ejected and reinserted, FatFS can no longer read any files.

I have tried unmounting the disk on ejection using f_mount(0, "", 0)

I also tried SD_HostDeinit() on eject and then reinit on insertion, but these don't seem to work.

The SDK example doesn't seem to handle reinsertion at all.

What is the correct way to handle eject/insert of the SDcard while the MCU is running?

Re: How to handle SD card eject & reinsert?

jackking — Fri, 14 Feb 2020 02:23:02 GMT

I am still banging my head on this.

Hopefully someone has dealt with this same issue? I would assume it is a really common requirement.

Re: How to handle SD card eject & reinsert?

jingpan — Fri, 14 Feb 2020 10:04:44 GMT

Hi Jack,

I made a demo base on the example evkmimxrt1060_fatfs_usdcard. It seems you don't need to do anything after desert. The files in SD card is created by original fatfs_usdcard project.

Regards,

Jing

Re: How to handle SD card eject & reinsert?

jackking — Sat, 15 Feb 2020 16:11:29 GMT

My test case is a little different.

I see in your example you did not MKFS and create the files on first insertion, assuming they were created some other time:

In my example I create the filesystem and files on first insertion each time and then the reinsert fails.

I have modified your example and tested, here is the output:

I am attaching the modified project, which I also changed to use semihosting with a J-Link, linked to RAM.

Re: How to handle SD card eject & reinsert?

jingpan — Tue, 25 Feb 2020 07:08:57 GMT

Hi,

It is strange. You code works fine on my board.

Can you try another card?

Regards,

Jing

Re: How to handle SD card eject & reinsert?

jackking — Fri, 28 Feb 2020 18:20:42 GMT

OK, I think I found and resolved my issue. It appears that the SDK is missing some functionality, specifically for managing the Card Detect of a MicroSD card. I am using a MicroSD card in an adapter.

Please see the following thread for details: https://community.nxp.com/message/1272833?commentID=1272833#comment-1272833

Essentially, I had to add the function to turn off the DAT3 pull-up for card detect. That is why it was failing on reinsert.

After adding this, the card can be reliably read again after reinsert!