I am using STM32H7A3 board and integrated an SD card using SPI. I am trying to transfer a large file and found that in first card if the number of sector to read is coming as 64, read works upto sector 36.

[JJoy.1]

After 36, it will give error and exited from code.

I tried another card , the code will set the sector count to 16 and loops through it to make the read complete. As i am trying a large file, its taking so much time.

I just want to know, is the sector count ( 16 and 64 for the 2 cards) is solely dependent on card and whether i can change from code. What is the relevance of sector 36 if sector count is 64. Anybody please clarify these things...

Attached code for reference. Above I refer( 64 and 16) the value of cc in file ff.c ( line no.3557)

Thanks,

Jestina

[Tesla DeLorean]

Could it relate to the cluster size being used by the file system on specific cards?

Perhaps look at those via "Properties" in Windows, or the metrics FatFs can provide.