Antonelli, Terry, Stout & Kraus
Fixed-length packet switching system adapted for function test
 An ATM exchanger includes a plurality of switch units connected in multiple stages, in which a circuit is provided for writing a test cell pattern into and reading it from a buffer memory of each switch unit in accordance with an instruction from a controller, so that the test cell read from the buffer memory can be transferred appropriately to the controller. 
Hitachi ULSI Engineering Corp. Hitachi, Ltd.
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Takahiko Kenichi Nobuhiro
Kozaki Asano Horie