AnsweredAssumed Answered

USB MSD FAT demo hangs

Question asked by Marlon Smith on Oct 24, 2013
Latest reply on Jul 18, 2014 by Raleigh Illgen

Hi everyone,


I'm running the usb msd demo with a k20 chip to try and read a file from a USB drive.  When I insert the drive, it is recognized as attached, and fat_demo() is called.


Near the start of fat_demo(), there are several disk_ioctl() calls.  The section of code looks like this:


/* Send some SCSI requests first */





res = disk_ioctl(0, UFI_INQUIRY_CMD, NULL);
res = disk_ioctl(0, UFI_INQUIRY_CMD, NULL);
res = disk_ioctl(0, REQUEST_SENSE_CMD, NULL);
//res = disk_ioctl(0, UFI_TEST_UNIT_READY_CMD, NULL);       /* On some devices UFI_TEST_UNIT_READY_CMD may fail*/  
res = disk_ioctl(0, UFI_READ_FORMAT_CAPACITY_CMD, NULL);
res = disk_ioctl(0, UFI_READ_CAPACITY_CMD, NULL);


As you can see there are several disk_ioctl calls.  The code always hangs on the second one (res = disk_ioctl(0, UFI_INQUIRY_CMD, NULL);), and seems to be spinning in the _usb_khci_task() function.


Has anyone else had this problem? If I commend out that particular line, the code just hangs on the next one. It somehow makes it through the first disk_ioctl call though.