Fujitsu fi-4220C Operator's Manual page 177

*3) The scanning speed is the maximum speed of the scanner
hardware. Software processing time such as data transfer time
is added to the actual scanning time.
*4) The scanning speed noted is the value when using the ADF to
scan.
*5) The maximum stacking capacity varies according to the
document thickness. For details, see "Chapter8, ADF AND
PAPER SPECIFICATION."
*6) The SCSI-2 and USB1.1 interfaces cannot be used at the same
time.
148 9.1 Basic Specifications