Exhibit 99.1

FOR IMMEDIATE RELEASE                                             April 13, 1999

CONTACT:  Donald L. Rich, President & CEO                         (408) 496-0474


Castelle Reports on Nasdaq Listing Status

Santa Clara,  Calif.,  April 13, 1999 - Castelle (Nasdaq:  CSTL) today announced
that the Nasdaq Listing Qualifications Panel approved its request to be moved to
The Nasdaq  SmallCap  Market  effective April 14, 1999 and its common stock will
continue  to be listed via an  exception  from the one dollar  minimum bid price
requirement.

While Castelle failed to meet this  requirement as of April 9, 1999, the Company
was granted a temporary exception from this standard subject to Castelle meeting
certain conditions. The exception will expire on July 14, 1999. In the event the
Company is deemed to have met the terms of the  exception,  it shall continue to
be listed on The Nasdaq SmallCap  Market.  The Company believes that it can meet
these conditions,  however,  there can be no assurance that it will do so. If at
some  future  date the  Company's  securities  should  cease to be listed on The
Nasdaq  SmallCap  Market,  they may  continue  to be listed on the  OTC-Bulletin
Board.  For the duration of the exception,  the Company's  Nasdaq symbol will be
CSTLC.

Castelle  is  headquartered  in Santa  Clara,  California  and can be reached at
800/289-7555, 408/496-0474 or www.castelle.com.

Forward-looking  statements in this release are made pursuant to the safe harbor
provisions of the Private  Securities  Litigation Reform Act of 1995.  Investors
are  cautioned   that  such   forward-looking   statements   involve  risks  and
uncertainties,  including,  without  limitation,  continued  acceptance  of  the
Company's products,  increased levels of competition,  new product introductions
and technological  changes, the Company's dependence upon third party suppliers,
intellectual  property rights and other risks detailed from  time-to-time in the
Company's periodic reports filed with the Securities and Exchange Commission.

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