The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 17, 1997
Filed:
Oct. 19, 1992
John A Langan, Austin, TX (US);
Thomas J Poterek, Austin, TX (US);
James L Broseghini, Austin, TX (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A method and apparatus for unstacking registers in a data processing system (100). In one form, the present invention is a more time efficient solution to the problem of unstacking and stacking registers (154-158) during interrupt processing in a data processing system (100). By taking advantage of the fact that pulling a register value off of the stack does not change any of the values stored in the memory which is being used as the stack, the present invention reduces the unstacking and stacking each time that two interrupts are processed back to back with no non-interrupt processing in between. The present invention eliminates the unstacking of the program counter register (158) and the restacking of registers (154-158) by changing the value of the stack pointer register (161) without any corresponding stacking or unstacking operation.