Versatile data shifter with sticky bit generation capability
US4901263A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 1988 |
| Grant date | Feb 13, 1990 |
| Priority date | — |
| Expiry date | Sep 12, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F7/49952
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A barrel-shift data shifter structure is modified to segregate switches in a switching matrix included therein into those switches as participate in a simple shift as well as in a barrel shift and those switches used only in a barrel shift. The former set of switches is controlled by shift control signals alone, and the latter set of switches responds to shift control signals and to the presence or absence of a rotation enable signal. The number of switches required is substantially smaller than required in a barrel shifter followed in cascade by a simple data shifter. Preferably provision is made for sticky bit generation. The sticky bit is the LOGIC OR response to all bits shifted to less significance than output data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.