Serial/Parallel/V.35 Cables

Parallel Printer Cables: Bi-directional and Centronics
IBM PC Compatible Serial Cables
Apple Compatible Serial Cables
Modular Cables & Adapters
Gender Changers / Mini Gender Changers
Serial, Parallel and Video Adapters
Introduction to Serial Standards

  Serial data transmission is the most common method of transmitting data from one work station to another. Information is broadcast from one source to another, one bit at a time, over one channel. Computers assimilate data by passing it through a serial interface; thereby trans- forming it into usable serial data. Then it passes through various ports, cables, and connectors that link the various devices.

RS-232C
There are three types of RS-232C connections; electrical, functional, and mechanical. The most commonly used is the D-shell, 25 pin or DB25 which normally connects work stations, etc. to peripherals like modems, converters, etc. There are two leads involved; a transmit and receive lead.

RS-449C
RS-449 normally refers to synchronous transmissions employing binary data transmission modes. It identifies signals that correspond to certain pin number assignments for use with DB37 and DB9 connectors.

CCITT
CCITT (now ITU) V.35 is the international standard called "Data Transmission at 48 Kbps using 60-108 Khz Group-Band Circuits.) Normally used for work stations and peripherals that interface with a high speed digital carrier, such as AT&T Dataphone Digital Service- (DDS).

RS-530
RS-530 supercedes RS-449 and supports RS-232. Based on the 25-pin connection, it operates with both RS-422 or RS-423. It further defines the variety of mechanical/electrical interfaces between computers/ workstations that transmit binary serial data (synchronous or asynchro- nous). RS-530 provides the means to obtain higher data rates when used with the standard RS-232 connector.

RS-422
RS-422 defines any balanced interface without any physical intercon- nection. This standard refers to any of the wide variety of connectors employed such as DB9, DB25 with non-standard pinning; DB25 fol- lowing RS-530, and DB37 following RS-449. RS-422 is commonly used in point-to-point communications. Binary signals can run at high speeds over long distances.

RS-485
RS-485 is similar to RS-422 except that transmissions are three way instead of two way. Commonly used in applications where one work station controls multiple peripherals. Up to 64 devices may be con- nected using this method.

V.35 assemblies are used primarily in high speed modem applica- tions. The V.35 cable assembly is a shielded 34 conductor inter- face and is available in plenum and non-plenum versions. Custom lengths and special wiring configurations as well as hybrid style assemblies are also available.