Atari SIO2USB User Manual page 32

$21 FAT-structure error on USB memory
$22 Internal memory is not configured
$23 USB device is not configured
$24 FAT sector at internal memory is not readable or writable
$25 FAT sector at USB device is not readable or writeable
$26 FAT file or directory is Read Only
$27 Requested ATARI sector is not inside the image
$28 Illegal Data frame length
$29 Received PERCOM density does not match to the image length
$2A Directory entry number is out of range
$2B USB device can't be enumerated
$2C Media capacity can't be read
$2D Unexpected command length byte
$2E Unexpected command content
$32 USB device is not mounted
$33 Internal memory is not mounted
$34 FAT Filename or directory name has zero length or is longer than
12 characters or name is longer than 8 character or extender is
longer than 3 characters
$35 No such directory or filename found
$36 Unexpected structure at mount, enable, disable command
$37 Filename / directory already exists or double mount error
$38 Not enough free memory available
32 Chapter 8 Error Codes SIO2USB User Manual