Avision AV626C - Manual (Page 36)

7-4
Question: Why some parallel port devices and
software’s keypro do not work with the
button scanner?
Answer: The scanner do pass-through printing all
right , but the pass-through printing may
not work if you connect the parallel port
with devices other than printer. Therefore,
if you would like to connect some parallel
port devices other than printer, please do
not connect them to the same parallel port
that the scanner currently uses. It is
suggested to use other parallel ports to
connect these devices or keypro. For
instance, you can connect the scanner to
LPT1, and connect other parallel port
devices to LPT2. Or you can add a data
switch to avoid the problem.