Four-Bit Look-Ahead Mask Generator
Original Publication Date: 1983-Jun-01
Included in the Prior Art Database: 2005-Feb-07
This article describes a look-ahead mask generator which has a substantial improvement in access time. 32-bit mask generators have been required for selective applications. Generally such mask generators have had a first set of lines 10 feeding a first set of true/complement generators 11 and a second set of control lines 12 feeding a second set of true/complement generators 13. These two sets of control lines feed the mask generator to produce the desired field pattern for 32 bits. One of the true/complement bit generators, say, generator 11, drives 32-bit decoders 14, while the other set 13 drives 32-bit decoders 15. On the output, the 32-bit field is variable and dependent upon the input states of two sets of control lines. The 32-bit field pattern consists of ones surrounded by zeros.