05128559 is referenced by 192 patents and cites 5 patents.

A standard logic block, or macrocell, is provided for use on programmable logic devices. The macrocell uses RAM to perform logic functions, and further includes circuitry which allows writing of data to the RAM during use. Each logic block can be configured at programming time to be either a user RAM, allowing the user to write data to such memory during use, or configured as performing logic functions. The contents of macrocells configured as providing logic functions cannot be changed except by reprogramming the device.

Title
Logic block for programmable logic devices
Application Number
414695
Publication Number
5128559
Application Date
August 8, 1991
Publication Date
July 7, 1992
Inventor
Randy C Steele
Southlake
TX, US
Agent
Richard K Robinson
Lisa K Jorgenson
Kenneth C Hill
Assignee
SGS Thomson Microelectronics
TX, US
IPC
H03K 19/177
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