Programmable hardware mailbox message technique and system

Abstract

A mailbox message system is coupled between a processor having a mailbox and one or more peripheral devices or circuits communicating information to the processor. The mailbox message system in the present invention reports events which occur in the peripheral devices or circuits to the mailbox within the processor to be serviced by the processor. The mailbox message system receives inputs from the processor indicating which events are allowed to be currently serviced by the processor and stores these inputs in a first memory. The mailbox message system further receives unique signals representing distinct events from the peripheral devices and stores these signals in a second memory. The generated events which are pending service in the second memory are then compared with the allowed events in the first memory. When a match exists, a message is encoded and transmitted to the mailbox of the processor indicating that the processor has an event to be serviced. The processor then must service all the pending events in the second memory.