Adder for exponent arithmetic

Details Adder for exponent arithmetic Adder for exponent arithmetic

1981-01-02

1982-12-28

Smith, Jerry

Boots, shoes, and leggings

364737, G06F 748

Patent

active

043665489

ABSTRACT:
A characteristic adder for use in a data processing system that performs floating-point arithmetic operations is described. A 1's complement subtractive adder is shown for forming the sum or difference of a pair of exponents under control of function control circuitry, along with an indication of which characteristic is larger for selecting which mantissa operand should be shifted for proper alignment. The function control circuitry responds to function signals to select addition or subtraction, provide the magnitude or complement of the results, and select between two available floating-point formats. Characteristic Overflow and Underflow is tested and signaled for each of the two possible floating-point formats.

REFERENCES:
patent: 3814925 (1974-06-01), Spannagel
patent: 3829673 (1974-08-01), Bouton, Jr. et al.
patent: 3871578 (1975-03-01), Van De Goor et al.
patent: 4161784 (1979-07-01), Cushing et al.
patent: 4282581 (1981-08-01), Bondurrnt et al.
patent: 4305134 (1981-12-01), Joyce et al.
patent: 4319335 (1982-03-01), Rubinfield
Litwak et al.: "Exponent Update and Latch in Three Levels", pp. 598-599, IBM Tech. Journal, vol. 9, No. 6, Nov. 1966, Armonk, New York.
J. E. Thornton: "Design of a Computer-The Control Data 6600", pp. 77-84, Scott Foresman & Co.-Glenview, Ill.
Davis, "The Illiac IV Processing Element", pp. 800-816, IEEE Transactions on Computers: vol. C-18, No. 9, Sep. 1969, see pp. 809-811, New York, New York.
Anderson et al.; "The IBM System 360 Model 91: Floating Point Execution Unit", IBM Tech. Journal, vol. 11, No. 1, Jan. 1967, pp. 34-53-See pp. 38-40 and FIG. 3; Armonk, New York.

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