Method for resolving conflicts between interrupt sources sharing the same priority level

A method for controlling a processor in a data processing system so that multiple events are serviced on a single interrupt level. On the occurrence of a first interrupt request the processor is forced to run the routine that services the interrupt in a background mode. This is accomplished by immediately clearing the interrupt source, thus permitting the processor to accept new interrupt requests on the same level. On the occurrence of a second interrupt request, at the same level, the processor branches from executing the first interrupt routine on the background mode to service the second interrupt request on an interrupt level or foreground mode.