05089973 is referenced by 41 patents and cites 29 patents.

Programmable logic cells, and arrays of those cells, having certain characteristics, including: (1) the ability to program each cell to act either as a logic element or as a logical identity element(s) between one or more inputs and one or more outputs; (2) the ability to rotate circuits by 90.degree. and to reflect circuits about horizontal and vertical axes; (3) an integrated logic and communication structure which emphasizes strictly local communications; (4) a minimal complexity of logic functions available at the cell level, making available a very fine-grained logic structure; and (5) suitability for implementation of both synchronous and asynchronous logic, including speed-independent circuits. Cells are arranged in a grid, with each cell communicating with its north, east, west and south neighbors. The cells are programmable to several states. Using a graphics-based programming environment, the user may construct systems at a pictorial block diagram level, rather than having to be concerned about the detailed implementation of the internal structure of each block. Blocks may be rotated and they may be reflected about horizontal and vertical axes, to place their input and output connections on different sides and positions without altering the internal electrical operation of the blocks.

Title
Programmable logic cell and array
Application Number
928527
Publication Number
5089973
Application Date
July 11, 1989
Publication Date
February 18, 1992
Inventor
Frederick C Furtek
Arlington
MA, US
Agent
Pennie & Edmonds
Assignee
Concurrent Logic
CA, US
Apple Computer
CA, US
IPC
H03K 17/693
G06F 15/60
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