USER PROGRAMMABLE INTERRUPT MASK WITH TIMEOUT

A method and apparatus for implementing a user programmable interrupt mask and timeout count. A master mask latch receives non-privileged instructions which alternatively cause the latch to disable and enable interrupt requests for the processor. The non-privileged disable interrupts instruction additionally causes the initiation of a timeout counter for defining the duration of an interval for which interrupt requests may be disabled. The non-privileged enable interrupts instruction additionally terminates the count of the timeout counter. If the timeout counter is not halted within the defined interval, a system error interrupt is generated, interrupts are re-enabled and the counter is halted. In a further embodiment, the disable interrupts instruction may be incorporated into a fetch and hold instruction and the enable interrupts instruction may be incorporated into a store and release instruction to facilitate atomic read, modify, write operations.