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US4665500A Expired / Lapsed US ⏱️ 0.0 years remaining

Multiply and divide unit for a high speed processor

Assignee: Texas Instruments Inc
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Filing: 1984-04-11
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Granted: 1987-05-12
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Expires: 2004-04-11
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Abstract

Abstract A High Speed Multiplier/Divider for use with high speed processors that have dedicated adders, registers, controls and logic for performing a multiply operation, a multiply and add operation, and a divide operation. The multiply/divide circuit has capability of multiplying a 16 bit word times a 16 bit word that produces a 32 bit product with divide being the inversed of the multiplication operation and may use signed or unsigned multiply/divide. A Booth algorithm is used to implement the multiply operation and the multiply/divide operations are operating asynchronous, that is, at the completion of one set of operations, the next set is implemented.

Inventors

  • 👤 Sid Poland

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 10:18
CPC Classifications
G; G06; G06F; G06F7/00; G06F7/38; G06F7/48; G06F7/52; G06F7/523; G06F7/533; G06F7/5334; G06F7/5336; G06F7/535; G06F7/544; G06F7/5443; G06F2207/00; G06F2207/535; G06F2207/5353; G06F7/499; G06F7/49905; G06F7/49994

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 463 words
A multiply and divide unit for a high speed processor for performing a programmed mathematical operation on a first argument with a second argument to obtain a result thereby, the multiply and divide unit being responsive to a programmed instruction applied to the high speed processor and comprises: operation means for controlling a mathematical operation to be performed on the first and second arguments as instructed by the program instructions; first output register for registering a first part of the result of the mathematical operation; second output register for registering a second part of the result of the mathematical operation; A means for obtaining an A word from the first argument; first B means for obtaining a first B word and a first B compliment from the second argument and the first part; second B means for obtaining a second B word and a second B compliment word from the first B word; third B means for obtaining a third B word and a third B compliment word from a U word; fourth B means for obtaining obtaining a fourth B word and a fourth B word compliment from the first B word; recoder means for performing a Booth recode on the A word to obtain a Booth recoded A word; B selector means responsive to the Booth recoded A word for selecting a B word from the first B word, first B word compliment, second B word, second B word compliment, third B word, third B word compliment, forth B word, and fourth B word compliment; first selector means for selecting an A argument from the A word, the first B word, the second part, or a zero word; second selector means for selecting a B argument from the zero word, the B word, and the first part; adder means for adding the A argument and B argument to obtain a first summation word; more selector means for selecting the U word from the first summation word and the second part; least selector means for selecting a V word from the first summation word or the first part; modification means for modifying the V word to obtain a modified V word and includes a shift means for replacing a predetermined number of bits in the V word with a first logic state; first part selector means operatively connected to the first output register for selecting the first part from the U word and the modified V word; second part selector means operatively connected to the operations means for providing to the second part to the second output register selected from the U word, a modified U word, a first modified second part, and a second modified second part; and data bus for applying the zero word to the first and second selectors.
Claim 2
Dependent Claim 463 words
A multiply and divide unit for a high speed processor for performing a programmed mathematical operation on a first argument with a second argument to obtain a result thereby, the multiply and divide unit being responsive to a programmed instruction applied to the high speed processor and comprises: operation means for controlling a mathematical operation to be performed on the first and second arguments as instructed by the program instructions; first output register for registering a first part of the result of the mathematical operation; second output register for registering a second part of the result of the mathematical operation; A means for obtaining an A word from the first argument; first B means for obtaining a first B word and a first B compliment from the second argument and the first part; second B means for obtaining a second B word and a second B compliment word from the first B word; third B means for obtaining a third B word and a third B compliment word from a U word; fourth B means for obtaining obtaining a fourth B word and a fourth B word compliment from the first B word; recoder means for performing a Booth recode on the A word to obtain a Booth recoded A word; B selector means responsive to the Booth recoded A word for selecting a B word from the first B word, first B word compliment, second B word, second B word compliment, third B word, third B word compliment, forth B word, and fourth B word compliment; first selector means for selecting an A argument from the A word, the first B word, the second part, or a zero word; second selector means for selecting a B argument from the zero word, the B word, and the first part; adder means for adding the A argument and B argument to obtain a first summation word; more selector means for selecting the U word from the first summation word and the second part; least selector means for selecting a V word from the first summation word or the first part; modification means for modifying the V word to obtain a modified V word and includes a shift means for replacing a predetermined number of bits in the V word with a first logic state; first part selector means operatively connected to the first output register for selecting the first part from the U word and the modified V word; second part selector means operatively connected to the operations means for providing to the second part to the second output register selected from the U word, a modified U word, a first modified second part, and a second modified second part; and data bus for applying the zero word to the first and second selectors.
Claim 3
Dependent Claim 58 words
The multiply and divide unit according to claim 1 wherein the A means comprises: means means for selecting the A word from the first argument and a compliment of the first argument; means for obtaining the compliment of the first argument including means for shifting a predetermined number of bits of the A word in a first direction.
Claim 4
Dependent Claim 44 words
The multiply and divide unit according to claim 1 wherein the first B means comprises: first B selector means for selecting the first B word from the first part or the second argument; and register means for obtaining a compliment of the B word.
Claim 5
Dependent Claim 65 words
The multiply and divide unit according to claim 3 wherein the second B means comprises: means for shifting the first B word a second predetermined number of bits in a second direction to obtain the second B word thereby; and means for shifting the first B compliment word the second predetermined number of in the second direction to obtain the second B compliment word thereby.
Claim 6
Dependent Claim 65 words
The multiply and divide unit according to claim 3 wherein the fourth B means comprises: means for shifting the first B word a third predetermined number of bits in a second direction to obtain the fourth B word thereby; and means for shifting the first B compliment word the third predetermined number of in the second direction to obtain the forth B compliment word thereby.
Claim 7
Dependent Claim 30 words
The multiply and divide unit accordinbg to claim 1 further comprising: register means operatively connected to the first part selector for registering over flow conditions of the first output register.

References Cited (Backward Citations)

US3293420A Cited
US3761698A Cited
US4153938A Cited
US4337519A Cited
US4238833A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-05-11 1990-11-10 1991-05-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-05-11 1994-11-10 1995-05-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-05-11 1998-11-10 1999-05-12 $7700.00 Window Closed / Lapsed

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