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:
Feb. 14, 1989
Filed:
Oct. 17, 1985
Jan S Wesolowski, Redwood City, CA (US);
Ampex Corporation, Redwood City, CA (US);
Abstract
A serial data communication system including a microprocessor and an asynchronous communication interface adapter (ACIA) implementing a SMPTE Supervisory Protocol for Digital Interface Control. The system detects the beginning of a break character as the first framing error which occurs after the last word of a data block has been detected. The receive clock of the ACIA is disabled in response to the start of break detection by the software reset of a bistable device which disables a receive clock gate. The framing error detection circuit of the ACIA is additionally disabled by the termination of the receive clock signal. The end of the break character is detected as the space to mark transition before the start of the first word in the data block. The receive clock is enabled by setting the bistable device with the end of break transition thereby detecting the termination of the break character and enabling the receive clock gate. This operation correctly restarts the frame timing circuit of the ACIA at the start bit of the first word of a data block.