Three input arithmetic logic unit with controllable shifter and

Details Three input arithmetic logic unit with controllable shifter and Three input arithmetic logic unit with controllable shifter and

1995-06-07

1997-05-27

Auve, Glenn A.

Boots, shoes, and leggings

395376, G06F 738

Patent

active

056340656

ABSTRACT:
A three input arithmetic logic unit (230) that generates a combination of the three inputs that is selected by a function signal. The second input signal comes from a controllable barrel rotator (235). The rotate amount is a default rotate amount stored in a special data register, a predetermined set of bits of data recalled from a data register or zero. A one's constant source (236) is connected to the barrel rotator (235) to supply a multibit digital signal of "1". This permits generating a second input signal of the form 2.sup.N, with N being the rotate amount. The output of the barrel rotator (235) may be stored independently of the arithmetic logic unit (230) result. The third input signal comes from a multiplexer (233) that selects between an instruction specified immediate field, data recalled from a data register or a mask input from a mask generator (239). One preferred form of the mask has a number of right justified 1's corresponding to a mask input signal. This mask input signal may be the default barrel rotate amount or a predetermined number of the least significant bits of a third input signal as selected by a multiplexer. A second preferred form of the mask is selected one of the left most 1, the right most 1, the left most bit change or the right most bit change of a predetermined set of the least significant bits of data recalled from a data register.

REFERENCES:
patent: 4785393 (1988-11-01), Chu et al.
patent: 5146592 (1992-09-01), Pfeiffer et al.
patent: 5301341 (1994-04-01), Vassiliadis et al.

Affiliated with

Also associated with

Rating

Three input arithmetic logic unit with controllable shifter and does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Three input arithmetic logic unit with controllable shifter and , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Three input arithmetic logic unit with controllable shifter and will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2336406