The return value of f_read function in FATfs system is FR_INVALID_OBJECT

反倒是fdsf

The return value of f_read function in FATfs system is FR_INVALID_OBJECT [Copy link]

The function of the code in the red box in the figure is to store the data of the mp3 audio file in databuf so that it can be sent later. Through the single-step test, the res return value is 0x09, and the error is FR_INVALID_OBJECT. The test enters the f_read() function and checks that the value of fil->fs->fs_type is 0, so FR_INVALID_OBJECT is returned. However, fs_type is 0, which means that it is not mounted. I have already mounted the SD card in the main function. What is going on? I also attached the complete code. Please help me take a look when you have time. Thank you.

muxb

You can try changing the third parameter of mount to 0.

反倒是fdsf

muxb posted on 2019-1-24 08:57 You can try to change the third parameter of mount to 0.

No, it still returns the error value FR_INVALID_OBJECT

反倒是fdsf

I found that fil->fs->id and fil->id are both 1. Logically, the one I mounted is 0, so it should be 0, right?

反倒是fdsf

There’s no one here.

yubinwu

A similar situation occurred with the landlord

Basically it has nothing to do with FF_MAX_SS, since it is already set to 4096.

In my case, if FF_MAX_SS is set to 512 by default and is not changed, a hardware fault will occur.

It may be related to Stack. After increasing 4096, that is, FF_MAX_SS length, it is normal to change from the original 0x200 to the following value

Stack_Size EQU 0x00001200

The reason may be that the data was flushed by the stack operation and rewritten

Freaks124

Has the landlord solved this problem?