Avision AV620C - Manual (Page 36)

6-4
Question: Why some parallel port devices and
software’s keypro do not work with the
AV620C?
Answer: The AV620C can 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 AV620C currently
uses. It is suggested to use other parallel
ports to connect these devices or keypro.
For instance, you can connect the AV620C
to LPT1, and connect other parallel port
devices to LPT2. Or you can add a data
switch to avoid the problem.