VisiCom retargeting process and NTDS help Navy battle obsolescence

May 1, 2000
SAN DIEGO - Engineers at VisiCom, a Titan company in San Diego, are using their Rapid Retargeting process - based on programmable logic devices - to improve their audio signal boards for the U.S. Navy

By John McHale

SAN DIEGO - Engineers at VisiCom, a Titan company in San Diego, are using their Rapid Retargeting process - based on programmable logic devices - to improve their audio signal boards for the U.S. Navy. The boards help Navy officials manage commercial-off-the-shelf (COTS) electronic obsolescence problems.

VisiCom officials also continue to invest in their VME MIL-STD 1397 Navy Tactical Data System (NTDS) I/O processors for long-term life cycle support in Navy vessels.

VisiCom's Rapid Retargeting process and audio boards are aboard:

  • Arleigh Burke class destroyers (DD 51);
  • the AN/SQQ-89 anti-submarine warfare suite to connect different subsystems;
  • the Acoustics-Rapid COTS Insertion program - better known as the A-RCI sonar upgrades; and
  • the future Virginia class new attack submarine (NSSN).

VisiCom experts are enhancing their VME audio signal processor boards to extend system life cycles.

"Our audio cards have been successfully implemented into a variety of customer systems for over six years," says Ron Hawkins, chief operating officer of VisiCom's Computer Products Division. "These same audio products are now planned to support both legacy and new production systems for at least another six years."

Engineers at a VisiCom customer, FlightSafety International Inc. of Flushing, N.Y., were using a VisiCom audio board for one of their flight simulators when a component became obsolete, Hawkins says. "The impact of any configuration change on these complex systems can be far reaching, resulting in expensive system redesigns and extended production schedules," Hawkins says.

"They were loathe to reconfigure a $20 million simulator for one component," so VisiCom experts applied their Rapid Retargeting process to their 4300 boards and saved FlightSafety substantial time and money with minimal software porting, Hawkins claims.

VisiCom engineers use their Rapid Retargeting process to create a VHSIC Hardware Description Language (VHDL) model of the existing digital logic on the cards to synthesize or "retarget" that logic onto field programmable gate arrays (FPGAs) and complex programmable logic devices (CPLDs).

They retargeted logic embodied in generic array logic and other obsolete devices onto one FPGA and one CPLD for their newly redesigned 4300 series of audio boards. VisiCom customers are realizing a faster time to market, continued ease of maintenance, and reduced costs over the life cycle of their system with the updated board, VisiCom officials say.

First, VisiCom engineers perform a thorough analysis of the system with electronic design automation tools for simulating system functions, explains Steve Williamson, lead engineer for VisiCom's Rapid Retargeting program. It is then synthesized into a FPGA design, he adds.

The process reduces spares and assembly costs, Williamson says. For example a printed circuit board that uses 70 different modules, each a couple of inches long, can be replaced with a board that has about five spares which are used to program the FPGA, he continues. That not only saves money, but real estate as well, Williamson adds.

Rapid retargeting provides a form, fit, and function replacement with a minimal effect on software costs, Hawkins says. The custom logic is what makes any software difficulties miniscule, he adds.

Circuitry modeling using VHDL provides several benefits to long life cycle management, VisiCom officials claim. The VHDL description results in improved design documentation for the board, and an extensive software-based simulation of major portions of the board.

The VHDL model, provides a "portable" design definition that can be mapped into other logic devices should the present devices become obsolete. VisiCom experts also added automated test capabilities to improve manufacturing throughput and help diagnose problems in boards that might be returned for repair in the future, VisiCom officials say.


Experts have said for years that NTDS is outdated, says Ozzie Monge, business development manager at VisiCom. Yet, VisiCom leaders are still supporting their original NTDS products from 10 years ago, he claims.

NTDS is here to stay, because all the ships in the U.S. Navy fleet are configured for it and reconfiguring for something new is a cost no one wants to pay, Monge maintains.

"We have been delivering NTDS I/O cards to the Navy, who has successfully implemented them in a variety of combat systems, such the [Aegis] AN/UYQ-70 Advanced Display System," from Lockheed Martin in Egan, Minn., Hawkins says.

For the military, life cycle support, performance, flexibility, and rapid deployment capabilities are key considerations when awarding a contract, Hawkins says. "VisiCom's NTDS I/O cards meet all these requirements," he claims.

Long life cycle management is a key issue for the Navy due to the extensive use of COTS in complex systems such as the Aegis weapons system aboard Arleigh Burke-class destroyers and Ticonderoga-class (CG 47) cruisers, says Robert Didden, display manager for the Naval Sea Systems Command (PMS-400). "VisiCom's support for extended COTS life cycles solves an important problem for us," he adds.

VisiCom engineers manage the life cycle of their NTDS products with application-specific integrated circuit (ASIC)-based replacements for the bit-slice microprocessor and companion chips used on cards from InnovASIC, Inc. of Albuquerque, N.M., Monge says.

InnovASIC engineers specialize in replacements for discontinued integrated circuits (IC), and are applying their MILES (Managed IC Lifetime Extension System) technology to develop the ICs required for VisiCom's cards.

The MILES process uses software, electronic design automation, and quick-turn ASIC technology to develop IC replacements and solve obsolescence problems, Monge says. HDL modeling and automated verification are core features of the process, which results in an IC with a virtually infinite life, VisiCom officials claim.

VisiCom engineers are currently working on a NTDS product for Aegis applications that works with longer cable lengths than they have used before, which were not in the original MIL-STD 1397 specifications, Monge says. The cable lengths are for health and safety reasons, Monge adds.

NTDS still has a maximum throughput of about one megabyte per second, and theoretically it can be designed to go faster, Monge says. However, speed is not the most important factor, and how fast it goes depends on its specific application, he says.

For more information on Rapid Retargeting and NTDS contact VisiCom by phone at 800-621-8474, by fax at 858-457-0888, by mail at VisiCom, 10052 Mesa Ridge Court, San Diego, Calif. 92121, or on the World Wide Web at

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