Advanced Protocol Analyzer Enhanced for FM0 Protocol.

GREENLAWN, N.Y.--(BUSINESS WIRE)--June 17, 1998--Telebyte Technology Inc. (OTCBB-TBTI) has just announced a major enhancement to the Model 905 Comscope Protocol Analyzer designed for use with any PC.

The enhancement allows the Model 905, a high performance serial data line monitor, bit error rate tester (BERT) and emulator, to support data communications protocols that use FM0 such as HDLC, SDLC and X.25.

The Comscope has been enhanced to include support for 'bi-phase space', or 'FM0' encoded data. FM0 encodes a '1' bit as a transition at the beginning of the bit cell and a '0' as a transition at the beginning and middle of the bit cell. FM0 encoding of HDLC packets (the kind used by protocols such as SDLC and X.25) is gaining in popularity because it offers several advantages, since there is at least one transition for each bit cell a Phase Locked Loop can be used to extract clock information from the data stream, so there is no need for separate data and clock lines.

These guaranteed transitions mean that the data line(s) can be inductively coupled providing isolation and noise immunity. Because data is encoded as frequencies the polarity of the data is irrelevant. The Comscope 905 will support FM0 encoded HDLC packets up to 230,400 bps. The Comscope also directly supports the RS-485 electrical interface, which is often the medium of choice for FM0 data.

The Model 905 PC Comscope is an external device that installs easily -- just connect the cable to the parallel port of the PC. The Model 905 is equipped with a complete range of built-in hardware interfaces, which include RS-232, RS-422, RS-485 and V.35. Selection of the desired interface is user defined under program menu selection. The PC Comscope operates in ASYNC, SYNC, HDLC or in a mode called UNKNOWN whereby any serial data can be accepted and deciphered.

Operating under control of a program running on the PC the Model 905 supports most WAN protocols, both asynchronous and synchronous. The synchronous capability includes SNA/SDLC, X.25/HDLC, Bisync and IPARS. The Model 905 captures the whole picture: Data, control leads, time stamps and error conditions. This enables the user to do extensive post-capture analysis of data, even at a different location. This capability includes trap or search for any combination of these events and not just data strings.

User access to the Model 905 is via a DB25 male connector on the rear panel. A DB25 female connector is provided to access the PC. The unit can be configured to be a DTE or DCE through software. Then status LED's display TD, RD, RTS, CTS, DSR, DCD, DTR, RI, Receive Clock and Transmit Clock.

The Model 905 PC Notebook Comscope is supplied with a convenient padded case to simplify carrying the unit and its accessories. This feature really makes the Comscope portable. The Model 905 sells for $798 each and is available from Telebyte or any of its worldwide network of distributors. For more information contact Telebyte Technology Inc., 270 Pulaski Road, Greenlawn, New York 11740, 1-800-835-3298, fax [phone], email: [e-mail] or visit Telebyte's web site at www.telebyteusa.com

CONTACT: Telebyte Technology Inc.

270 Pulaski Road

Greenlawn, New York 11740-1616

P: 516/423-3232 or 800-TELEBYT

F: 516/385-8184

Email: [e-mail]

Internet: www.telebyteusa.com