How to use a parallel port scanner and printer simultaneously
Solution: All scanners that use the parallel port have two parallel ports at the back panel. One is marked ‘To Computer’, and the other, ‘To Printer’. All you need to do is first detach the printer cable from the computer and reattach it to the scanner. Then take the scanner cable and attach it to the computer. This way the scanner mediates between the printer and your computer, and both devices can be used simultaneously.