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:
May. 16, 1995
Filed:
Apr. 08, 1994
Kevin V Roach, Carver, MA (US);
David C Littlejohn, Marshfield Hills, MA (US);
James G Calvin, Halifax, MA (US);
Interactive Process Controls Corp., Easton, MA (US);
Abstract
An interface circuit for use with process controllers permits analog signals to be input to a process controller through a binary interface of the process controller and permits analog signals to be output from the process controller through the binary interface. The input analog signal is converted to a digital sample of N bits. An identification pulse and the N bits of the digital sample are transmitted to the process controller at a rate selected for compatibility with the scan time of the process controller. The process controller includes a software routine for recognizing the identification pulse and the N bits of the digital sample. An equivalent approach is used for outputting analog signals through a binary interface of a process controller. The interface circuit can include multiple channels for inputting or outputting multiple analog signals.