Patent ID: 7281118

Claim:
A method for messaging between system processors and co-processors connected by a system bus comprising: storing a Message Control Block (MCB) in memory prior to system operation for each processor or co-processor connected to said system bus, said MCB identifying the physical address of said processor or co-processor, a memory location address for a response from said processor or co-processor to be stored, and a memory location of a message to be sent; creating a move to Device Control Register (DCR) command having a DCR pointer identifying said MCB; building a message for transfer to said processor or co-processor in memory at an address specified by said MCB, said message including said return address for a response message to be stored and having format information for said outgoing message; accessing with a Direct Memory Access (DMA) controller the MCB from the DCR command pointer; and sending the message identified in said MCB to said processor or co-processor.