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:
Sep. 14, 1982
Filed:
Sep. 05, 1979
Pern Shaw, Austin, TX (US);
Fuad H Musa, Austin, TX (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A single-chip microcomputer comprises a CPU (1), a RAM (2), a ROM (3), a timer (4), serial I/O communication logic (5), four I/O ports (11-14) and various power supply, clock, and control inputs. One of the I/O ports (13) is user programmable by application of specific signals to mode selection pins (P20-22) for configuration in several possible ways. The programmable port comprises a plurality of lines which each may be individually programmed as input or output lines to peripheral equipment associated with the microcomputer. Alternatively, the port lines can be programmed to serve as a bidirectional data bus to external memory. Alternatively, the port lines can be programmed to be multiplexed data and address lines to external memory. Bus arbitration logic is provided to route data to the CPU from either on-chip memory or external memory.