Epson ActionPrinter 4500X User Manual - Page 266

number systems Three number systems are commonly used with printers: binary is base 2 and uses only the digits 0 and 1. All information in computer systems is handled in binary form represented by electrical signals that are on or off. A binary digit is often called a bit; any decimal number between 0 and 255 can be expressed by an eight-bit binary number. decimal is base 10 and uses the digits 0, 1,2,3,4,5,6,7,8, and 9. (This is the most familiar system.) hexadecimal (hex) is base 16 and uses the digits 0, 1,2,3,4,5,6,7, 8,9, A, B, C, D, E, and F. This is frequently used by programmers. Any decimal number between 0 and 255 can be expressed by a two-digit hex number. on line When the printer is on line, it is able to communicate with the computer connected to it. paper-out sensor A small switch behind the platen that sends a signal when it is not in contact with paper, informing the printer and remote computer that there is no paper loaded, and causing the PAPER OUT light to go on. paper tension unit The part of the printer that fits above the platen to assure proper paper tension in the printing area. parallel interface An interface that connects the computer and the printer. A parallel interface transmits data one character or code at a time. See also serial interface. platen The black roller that provides the backing for the paper during printing. 6 Glossary