PC Hardware in a Nutshell, Second Edition

Parallel Connectors and Cables

IEEE 1284-1994 defines both the electrical and physical interface for cables and connectors. Cable quality is critical for IEEE 1284, because various IEEE 1284 modes support much higher transmission speeds than SPP.

Parallel Connectors

Traditional parallel cables use a DB25M connector for the PC end and a male, 36-pin, 0.085” centerline Champ connector with bale locks (commonly called a Centronics C36M) for the printer. The IEEE 1284-1994 specification allows these two traditional connectors to be used as before. It designates the DB25M the IEEE 1284-1994 Type A Connector and the C36M the IEEE 1284-1994 Type B Connector. IEEE 1284 also defines a new type of parallel connector, called the 1284-1994 Type C Connector, which uses a 36-pin, 0.050” centerline mini-connector with clip latches, and is usually called a mini-Centronics connector. Printer cables are now available that use these connectors in many combinations.

PC-to-Peripheral Parallel Cables

It used to be that a printer cable was a printer cable. Not anymore. Printer cables now come in a variety of types, which use different connectors and pinouts. The good news is that you can still use any printer cable to connect a PC to a printer—as long as the connectors physically fit—and that connection will work in some fashion. The bad news is that using an old printer cable may cripple the performance and functionality of the link.

When you buy a new parallel cable—which you should if you are now using ...