Hello, ST experts
STM32F417 is used on custom hardware design. And everything is OK except SD card. At first SD card works well. f_write takes about several milliseconds. But when the free space of SD card(San Disk Ultra 64GB) is less then e.g. 10GB, the f_write for about 5KB data takes more than 10 seconds. I add a timer count before and after f_write operation, and get this time interval.
Is there any suggestion about this issue?
Best Regards
Yang
