State machine standard cell that supports both a Moore and a Mealy implementation
US4691289A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 23, 1984 |
| Grant date | Sep 1, 1987 |
| Priority date | — |
| Expiry date | Jul 23, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2360/126
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A video system controller allows for the transfer of data between a display memory and a microprocessor that is used to control the controller and from the display memory to a CRT monitor. The transfer operations are controlled by the video system controller through a state machine that is configured with a plurality of standard cells connected in cascade arrangement, which can be configured as either a Moore or a Mealy state machine. Each state machine has a programmable logic array in which timing signals, when applied thereto, will cause a predetermined output to appear on the output on each of the standard cells. A logic means, depending upon whether the machine is a Moore type state machine or a Mealy type state machine logically manipulates the output of the programmable logic array to obtain the state output for that particular cell.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.