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:
Mar. 19, 1991
Filed:
May. 12, 1989
Timothy J Williams, Raleigh, US;
Ertugrul Baydar, Raleigh, NC (US);
Alcatel NA, Hickory, NC (US);
Abstract
An H4 byte generating algorithm is implemented by circuitry which includes counters for generating the H4 byte. The circuit is provisioned to indicate whether it is operating in a terminal multiplexer mode or an add-drop multiplexer mode. In the terminal multiplexer mode the counters are allowed to free run and continually produce successive H4 byte outputs. In the add-drop multiplexer mode selected counter outputs are compared with the received H4 byte and the number of mismatches is accumulated by a mismatch counter. When the mismatch counter reaches a predetermined number the value of the received H4 byte is loaded into the H4 byte counters and the mismatch counter is reset. Each time a proper match between H4 counter outputs and the received H4 byte is sensed, the mismatch counter is reset to 0. The presence of a red alarm will also result in the resetting of the mismatch counter and free running of the H4 byte counters.