Method For Performing A Division Operation In A System

• US 20090089346A1
• Filed: 09/28/2007
• Published: 04/02/2009
• Est. Priority Date: 09/28/2007
• Status: Active Grant

• Current Assignee: Lexmark International Incorporated (Ninestar Corporation)
• Original Assignee: Lexmark International Incorporated (Ninestar Corporation)
• Inventors: Moore, Jimmy Daniel JR., Bailey, James Ray, Fister, Zachary Nathan
• Granted Patent: US 8,103,712 B2
• Time in Patent Office: Days
• US Class Current: 708/204
• CPC Class Codes: G06F 2207/5355 Using iterative approximation not using digit recurrence, e.g. Newton Raphson or Goldschmidt
• CPC Class Codes: G06F 7/535 Dividing only

Abstract

A method for performing a division operation in a system includes a) determining an approximate quotient of a numerator value and a denominator value; b) determining an initial error of the approximate quotient; c) determining a quotient adjustment value based on the initial error; d) determining whether to apply the quotient adjustment value to the approximate quotient; e) if the determination at d) is YES, then applying the quotient adjustment value to the approximate quotient; f) determining an iterative error of the approximate quotient; g) updating the quotient adjustment value based on the iterative error; h) repeating acts d) through g) until the determination at d) is NO, thereby determining a final value for the approximate quotient; i) generating an integer quotient based on the final value of the approximate quotient; and j) using the integer quotient with regard to at least one aspect of the system.

Claims

1. A method for performing a division operation in a system, comprising:

a) determining an approximate quotient of a numerator value and a denominator value;

b) determining an initial error of said approximate quotient;

c) determining a quotient adjustment value based on said initial error;

d) determining whether to apply said quotient adjustment value to said approximate quotient;

e) if the determination at d) is YES, then applying said quotient adjustment value to said approximate quotient;

f) determining an iterative error of said approximate quotient;

g) updating said quotient adjustment value based on said iterative error;

h) repeating acts d) through g) until said determination at d) is NO, thereby determining a final value for said approximate quotient;

i) generating an integer quotient based on said final value of said approximate quotient; and

j) using said integer quotient with regard to at least one aspect of said system.

2. The method of claim 1, wherein a number of times said updating is performed is greater than or equal to zero.

3. The method of claim 1, wherein said system includes a processor used in performing said method, and wherein said processor does not include a native division function.

4. The method of claim 3, wherein said processor is an embedded processor resident in an application specific integrated circuit.

5. The method of claim 1, wherein said system is an imaging system, and said using said integer quotient is manipulation of image data.

6. The method of claim 1, wherein said system includes a print engine having a printhead carrier, and said using said integer quotient is a determination of a velocity of said printhead carrier.

7. The method of claim 1, further comprising performing a floating point division by:

converting said numerator value into a numerator binary fraction;

converting said denominator value into a denominator binary fraction;

expanding a precision of said numerator binary fraction by a predetermined amount to form an expanded numerator binary fraction;

shifting a decimal position in each of expanded numerator binary fraction and said denominator binary fraction to form a numerator integer and a denominator integer, respectively;

dividing said numerator integer by said denominator integer using the division process of acts a) through i) to generate said integer quotient;

converting said integer quotient into a floating point quotient; and

substituting said floating point quotient for said integer quotient in controlling said at least one aspect of said system.

8. A method for performing division in a system, comprising:

a) converting a numerator value into a numerator binary fraction;

b) converting a denominator value into a denominator binary fraction;

c) expanding a precision of said numerator binary fraction by a predetermined amount to form an expanded numerator binary fraction;

d) determining an approximate quotient of said expanded numerator binary fraction and said denominator binary fraction;

e) determining an initial error of said approximate quotient;

f) determining a quotient adjustment value based on said initial error;

g) determining whether to apply said quotient adjustment value to said approximate quotient;

h) if the determination at g) is YES, then applying said quotient adjustment value to said approximate quotient;

i) determining an iterative error of said approximate quotient;

j) updating said quotient adjustment value based on said iterative error;

k) repeating acts g) through j) until said determination at g) is NO, thereby determining a final value for said approximate quotient;

l) generating an integer quotient based on said final value of said approximate quotient;

m) converting said integer quotient into a floating point quotient; and

n) using said floating point quotient with regard to at least one aspect of said system.

9. The method of claim 8, wherein a number of times said updating is performed is greater than or equal to zero.

10. The method of claim 8, wherein said system includes a processor used in performing said method that does not include a native division function.

11. The method of claim 10, wherein said processor is an embedded processor resident in an application specific integrated circuit.

12. The method of claim 8, wherein said system is an imaging system, and said using said floating point quotient is manipulation of image data.

13. The method of claim 8, wherein said system includes a print engine having a printhead carrier, and said using said floating point quotient is a determination of a velocity of said printhead carrier.

14. An imaging apparatus, comprising a controller configured to receive image data, said controller executing program instructions for performing a manipulation of said image data by implementing a division operation including:

a) determining an approximate quotient of a numerator value and a denominator value;

b) determining an initial error of said approximate quotient;

c) determining a quotient adjustment value based on said initial error;

d) determining whether to apply said quotient adjustment value to said approximate quotient;

e) if the determination at d) is YES, then applying said quotient adjustment value to said approximate quotient;

f) determining an iterative error of said approximate quotient;

g) updating said quotient adjustment value based on said iterative error;

h) repeating acts d) through g) until said determination at d) is NO, thereby determining a final value for said approximate quotient; and

i) generating an integer quotient based on said final value of said approximate quotient.

15. The imaging apparatus of claim 14, wherein said controller has a processor used in performing said division, and wherein said processor does not include a native division function.

16. The imaging apparatus of claim 15, wherein said processor is an embedded processor resident in an application specific integrated circuit.

17. The imaging apparatus of claim 14, further comprising performing a floating point division by:

converting said numerator value into a numerator binary fraction;

converting said denominator value into a denominator binary fraction;

expanding a precision of said numerator binary fraction by a predetermined amount to form an expanded numerator binary fraction;

shifting a decimal position in each of expanded numerator binary fraction and said denominator binary fraction to form a numerator integer and a denominator integer, respectively;

dividing said numerator integer by said denominator integer using the division process of acts a) through i) to generate said integer quotient; and

converting said integer quotient into a floating point quotient.

18. The imaging apparatus of claim 14, further comprising:

a printhead carrier carrying at least one printhead;

a drive mechanism for moving said printhead carrier; and

a carrier position encoder configured to generate carrier position data representing a position of said printhead carrier,

said controller being communicatively coupled to said carrier position encoder, said controller executing program instructions for performing a determination of velocity of said printhead carrier using said division operation.