Patent ID: 6289391
Filing Date: 2001-09-11
Classification: G06F

Abstract:
In a heterogeneous computer system having at least two CPU's and a common memory completely accessible by at least one of said CPUs and being disposed for storing at least two different operating systems that actively run simultaneously and concurrently control resources of said heterogeneous computer system, a method for performing external procedure calls between a first program stored in said common memory and being executed by a first one of said CPU's under control of a first one of said two operating systems and a second program stored in said common memory and being executed by a second one of said CPU's under control of a second one of said two operating systems, said method comprising the steps of:a. said first program initiating said second program via a CPU-to-CPU signal bus between said at least two CPU's;b. said second program calling a specific function located in said first program via said CPU-to-CPU signal bus;c. said second program storing parameters, if any, in a second program stack having a portion thereof within said common memory;d. said first program fetching directly from said second program stack said parameters, if any, and converting them from a format compatible with said second operating system to a format compatible with said first operating system;e. said first program performing said specific function;f. said first program converting results of the preceding step, if any, from a format compatible with said first operating system back to a format compatible with said second operating system;g. said first program storing in a first program stack in having a portion thereof within said common memory said results to said second program; and,h. said second program fetching from said first program stack said results, if any.