Patent ID: 6286346
Filing Date: 2001-09-11
Classification: G06F,G16H,Y10T

Abstract:
In a medical device, a method of performing a requested routine of at least one of and combinations of multiplication and divisional operations including program suspension that indicates an interrupt command to trigger an interrupt service routine (ISR) subsequent to completing a most recent portion of the requested routine, for the at least one of and combinations of multiplications and divisional operations thereby performing the requested routine by a processor, the method comprising:providing the processor comprising a CPU interfaced with memory and further including a processor status word register storing an interrupt enable I-bit that may be set or not set, a register storing a conditional bit having a bit state that signifies whether a multiplication or division operation is enabled, a register storing an operand used in a multiplication or division operation, and an accumulator for storing the results of the multiplication and division operations, said CPU capable of performing a CPU normal program operations and an interrupt service routine (ISR) operation;executing a conditional instruction to add or subtract an operand addressed by the conditional instruction to stored contents of said accumulator and to store the result back in said accumulator if the conditional bit is in a predetermined conditional bit state;repeating the executed step a predetermined number of times;providing device operational circuitry for performing a medical device function that generates interrupts including a maskable CPU interrupt, to interrupt the CPU when prescribed medical device functions occur;suspending the executing step upon receipt of a maskable CPU interrupt if said I-bit in the processor status word register is set;executing the ISR operation in response to the receipt of the maskable CPU interrupt; andcompleting said requested routine for the at least one of and combinations of multiplication and divisional operations subsequent to completing said ISR operation.