The present invention relates to crystalline R-guanidines of -2-Ethoxy-3-{4-2-ethoxyphenyl}propanoate, its preparations and its use as therapeutic agents. The virtualized IO device includes programmed IO configuration registers corresponding to hardware resources, and a storage for storing a resource table that includes a plurality of entries. In a preferred embodiment, the real-time control strategy adjusts the engine air to fuel ratio AFR based upon an air to fuel ratio AFR gradient parameter.