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. 24, 1978
Filed:
May. 23, 1977
John T Adamchick, Schenectady, NY (US);
John C Sicko, Schenectady, NY (US);
Edwin C Underkoffler, Schenectady, NY (US);
General Electric Company, Schenectady, NY (US);
Abstract
A microcomputer controller for a printer, and apparatus for facilitating direct memory access to the microcomputer, includes a central processing unit (CPU) with a known set-up time at the beginning of each machine cycle. A memory, associated with the CPU, has an access time less than the CPU set-up time. A pair of three-state buffers are utilized on the address bus to, and the data bus to and from, the memory from each of the CPU and a direct memory access (DMA) port. A DMA control circuit is coupled to the three-state buffers to facilitate direct access to the memory, from the DMA port, during CPU set-up time intervals and also returns control of memory access to the CPU when the set-up, or synchronization, time interval ends. The microcomputer controller is utilized with additional memory, of the read-only type, and shift registers for realizing a printer controller capable of receiving print character data from the DMA port and causing that data to be printed as the associated symbol, indicia and the like, in a print font selected responsive to incoming data.