Abstract: A communication link protocol is provided for communicating between nodes of an interconnect system via a communication link. In one embodiment, the communication link protocol includes a direct memory access (DMA) command for writing a block of data from a local node to a remote node via the communication link; an administrative write command for writing data from a local node to registers in a remote node via the communication link for administrative purposes; a memory copy write command for writing a line of memory from a local node to a remote node via the communication link when any data is written into that line of memory; and a built in self test (BIST) command for testing the functionality of the communication link.

Abstract: A method is provided for communicating data in an interconnect system comprising a plurality of nodes. In one aspect, the method includes: issuing a command packet from a first node, the command packet comprising a respective header quadword and at least one respective data quadword for conveying a command to a second node, wherein the command is selected from a group comprising a direct memory access (DMA) command, an administrative write command, a memory copy write command, and a built in self test (BIST) command; receiving the command packet at the second node; issuing an acknowledgement packet from the second node, the acknowledgement packet comprising a respective header quadword for conveying an acknowledgement that the command packet has been received at the second node.