Content on this page requires a newer version of Adobe Flash Player.

Get Adobe Flash player

Bus Technology

VME Bus:

VMEbus is a computer bus standard, originally developed for the Motorola 68000 line of CPUs, but later widely used for many applications and standardized by the IEC as ANSI/IEEE 1014-1987. It is physically based on Eurocard sizes, mechanicals and connectors, but uses its own signaling system, which Eurocard does not define. It was first developed in 1981 and continues to see widespread use today.

SATTVA eTECH has extensive experience of designing and developing systems for our customers using the VME Bus Interface. We have provided VME based solutions for various applications for Defence and Industrial Automation applications.

The various VME based systems designed by us are:

  • Motorola Coldfire Based motherboards
  • Token Bus Controller Modems
  • VME based Ethernet Boards
  • Analog Input and Output modules


PROFIBUS (Process Field Bus) is a standard for field bus communication in automation technology and was first promoted (1989) by BMBF (German department of education and research).

PROFIBUS is the only field bus that can be used in equal measure in production automation and process automation and has since become a global market leader. Worldwide, over 20 million PROFIBUS devices are in use (as of 2007).

Controller–area network (CAN or CAN-bus) is a vehicle bus standard designed to allow microcontrollers and devices to communicate with each other within a vehicle without a host computer. It was designed specifically for automotive applications but is now also used in other areas.

SATTVA eTECH has used the Profibus and Canbus technologies in designing and development of Data acquisition systems for Intelligent Pumping systems. The Digital board was designed around Motorola ColdFire MCF5272 and ADSP 21065L. This board consisted of communication channels like RS232/485, USB, Ethernet, CAN bus and profibus.

Token Bus:

Token bus is a network implementing the token ring protocol over a "virtual ring" on a coaxial cable. A token is passed around the network nodes and only the node possessing the token may transmit. If a node doesn't have anything to send, the token is passed on to the next node on the virtual ring. Each node must know the address of its neighbour in the ring, so a special protocol is needed to notify the other nodes of connections to, and disconnections from, the ring.

SATTVA eTECH has used the Token Bus technology to design controller modems. The Token Bus Controller Modem is used in systems to integrate, modulate and demodulate the digital and RF signal between the various PLCs in the system. The Token Bus Controller Modem integrates the function of the single-channel, phase-coherent Frequency Shift Keying (FSK) physical layer. TBCM provides the three basic functions of the physical layer including data transmission to the coax cable, data reception from the cable and management of the physical layer