On the adapters female plug, which one is positive and which one is negative? A: The central ring is positive and the outer ring is negative.
Q: My Canon multi-function or Epson dot matrix won’t print. A: Set parallel port to ECP/EPP mode, reboot the computer then reinstall the drivers for the printers as the system requires. Q: I can only work with one default printer when using an HP 3100 and an HP 340. The software won’t switch the port, and only the printer which was locked on the PC boot up will print. After switching, the printer that worked no longer works. A: It does not autoswitch when you work with 1 PC to 2 printers. You will need to use the software or manually push the button to switch the port and choose the right software before you try to print. Q: I have a Dell computer and a PC, one of them prints but the other one does not. A: The Dell computer will only let you choose between PC or PS/2 for parallel port setting. The PS/2 is for ECP, so try to switch the cable and try again. Dell may not support ECP or EPP which may be the cause of the problem. try using the reset button when it doesn’t print.
