2024-01-16 05:11 PM
Hi Folks,
I'd like to find an example of accessing a USB drive using the STM32CubeIDE. I'm currently using the Nucleo-H7A3Zi-Q board.
I believe I have setup the hardware correctly using the device configuration tool but I can't seem to find a simple or concise example on how to develop the code.
I have downloaded the STM32Cube_FW_H7_V1.11.0 code and examples but it still seems more complicated than it should. I've looked at STM32Cube_FW_H7_V1.11.0\Projects\NUCLEO-H7A3ZI-Q\Applications\USB_Host\MSC_Standalone\ but I don't understand how (or what) to import into my workspace.
For a start I just want to be able to write a "Hello World" into a file on the USB key.
Anybody have a good tutorial or example I can use?
Thanks,
Richard
2024-01-17 03:10 PM
Thank you for you help. Maybe we can continue tomorrow.
2024-01-17 03:14 PM
We do.
2024-01-19 08:58 AM
Hi AScha, Just wanted to update you on my "issue". I have tried a new Nucleo-H7A3Zi-Q board, and a new USB stick. Still got the same results:
usb_status = 1
Appli_state = APPLICATION_READY
fresult = FR_OK
When I set up the project I used the default clock settings. The SYSCLK = 96MHz and the USB clock = 48MHz. Are these values acceptable?
Thanks again,
Richard
2024-01-19 09:14 AM
Update#1
I lowered the USB clock to 12MHz and now the variables are:
usb_status = 0
Appli_state = APPLICATION_START
fresult = FR_OK
So I think we can go to the next step. I'm not sure what that is.
2024-01-19 11:55 AM
Hi,
I think, it was ok before :
>>
usb_status = 1
Appli_state = APPLICATION_READY
fresult = FR_OK
SYSCLK = 96MHz and the USB clock = 48MHz
<<
USB needs fix clock 48M , from crystal source (HSE , 8MHz , i think) . 48 .
+
After (usb_status = 1) you should see in debug, when moving mouse to " USBfs " , the readed file info.
2024-01-19 12:14 PM
I changed the USB clock back to 48MHz.
I can see the USBfs variable. It shows the correct name of the USB stick = "USB_Drive". How do I see the file name that is on the USB stick? There is only one file. It is named kocour.txt.
2024-01-19 12:37 PM - edited 2024-01-19 12:39 PM
As i said : should work now.
You can now use it, i give an example :
if(usb_status>0) // if usb mounted
{
fresult = f_opendir(&dir,USBHPath); // main dir open
fresult = f_readdir (&dir, &file_info); // read first filename
}
-> see in debug, when moving mouse to " dir " , the readed dir info.
+
-> see in debug, when moving mouse to " file_info " , the readed file info.
( i wrote this already .... didnt you try ? )
2024-01-19 01:30 PM
I did try what you suggested. It is not making sense to me. There is only one file on the USB stick. It is named "kocour.txt". When I stop the program and use the debugger to look into the &file_info variable I see this for the fname:
Details:"System Volume Information", '\0' <repeats 230 times>
Default:0x24001232 <file_info+26>
Decimal:603984434
Hex:0x24001232
Binary:100100000000000001001000110010
Octal:04400011062
The USB stick does not have a directory name so the "dir" variable looks like this:
dir
Details:0x24000294 <USBfs+188> "ål"
Default:0x24000294 <USBfs+188> "ål"
Decimal:603980436
Hex:0x24000294
Binary:100100000000000000001010010100
Octal:04400001224
2024-01-19 01:47 PM - edited 2024-01-19 01:48 PM
Haaaaa - your silly windows system doing this...always put this useless directory on everything it gets .
so read more :
if(usb_status>0) // if usb mounted
{
fresult = f_opendir(&dir,USBHPath); // main dir open
fresult = f_readdir (&dir, &file_info); // read first filename
fresult = f_readdir (&dir, &file_info); // read next filename
}
- and do this only once !
2024-01-19 01:54 PM
That was it. I can now see the correct file name. Now that I can read a file name how hard is it to write data to the USB drive?
I assume that I have to "Open" the drive, then "Write data" to the drive and then "Close" the drive.
Do you have an example I can look at?