2-8 9845B/C Environmental, Installation, and Preventive Maintenance Requirements To remove a ROM: • Turn the power switch off. • Slide out and open the proper drawer. • Gently pull the ROM straight up. • Close the cover and slide the drawer in. Connecting Interfaces CAUTION ALWAYS SWITCH OFF THE COMPUTER WHEN INSERTING OR REMOVING INTERFACES. FAILURE TO DO SO COULD DAM- AGE THE EQUIPMENT. Peripheral devices are connected to the 9845 computer with an interface. An interface can be inserted into any of the four I/O slots in the back of the computer, as shown.