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:
Oct. 19, 1993
Filed:
Sep. 24, 1990
Martin B Pawloski, Gilbert, AZ (US);
Other;
Abstract
An 8051-based microcontroller system includes an 8051 microcontroller chip which is capable of directly addressing only 64k addresses, and which is capable of addressing two kilobyte pages using a three bit embedded address portion of instruction op codes, and also includes a program memory having substantially more than 64k locations and a program memory expander including circuitry for transferring the three bits of the embedded address into an extended address register in response to detection of an AJMP or ACALL instruction from the program memory and forcing predetermined states on a multiplexed address/data bus to prevent the 8051 microcontroller chip from recognizing the AJMP or ACALL instruction. The program memory expander also includes circuitry for incrementing or decrementing the contents of the extended address register in coordination with incrementing or decrementing of an extended address including a portion in a program counter of the 8051 microcontroller chip and a portion in the extended address register, and circuitry for applying the extended address register to address inputs of the program memory.