The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 08, 1997
Filed:
Mar. 08, 1995
Akira Maruyama, Kawasaki, JP;
Koji Aihara, Kawasaki, JP;
Fujitsu, Limited, Kanagawa, JP;
Abstract
A transmission test apparatus having a system-clock redundancy system for testing a transmission path is proposed. In the transmission test apparatus, a clock switching unit selects a proper one from a plurality of system clocks in response to a clock selection signal and supplies a selected system clock. A test-signal check unit performs a synchronization operation in which a first test pattern generated based on the selected system clock is synchronized with a test signal coming through the transmission path and compares the first test pattern with the test signal. A synchronization detection unit detects the synchronization between the first test pattern and the test signal by examining the comparison result of the test-signal check unit to produce a synchronization detection signal. An error counter performs a counting operation in which a number of unidentified bits is counted as error bits after receiving the synchronization detection signal. And, an initializing unit initializes, in response to the clock selection signal, the synchronizing operation in the test-signal check unit and the counting operation in the error counter.