1. A method for interfacing to an emulation device, the method comprising: receiving, with the emulation device, an instruction created as part of a function required by an emulation of a circuit design, wherein the instruction includes a field identifying the instruction as one of a plurality of potential data access mode instructions; identifying, with the emulation device, a target buffer from address data in the instruction; writing, with the emulation device, any payload data received with the instruction into the target buffer; executing, with the emulation device, one of the plurality of potential data access mode instructions identified in the field; wherein: for an instruction identified as a direct memory access mode instruction: if the instruction is a write command: writing the data in the target buffer to a memory system based on a target memory address provided in the instruction; if the instruction is a read command: reading data stored at a target memory address provided in the instruction to the target buffer; returning the data from the target buffer in a read response; for an instruction identified as a mode instruction other than a direct memory access mode instruction: if the instruction is a write command, using a processor associated with the target buffer, stepping through the data in the target buffer and executing any commands embedded in said data; if the instruction is a read command, returning the data from the target buffer in a read response; such that said emulating facilitates manufacture of an integrated circuit that includes said circuit design.