typedef enum {
    MPIControlMessageLIBRARY_VERSION,   /* Keep as first control message */
    MPIControlMessageADDRESS_INVALID,
    MPIControlMessageCONTROL_INVALID,
    MPIControlMessageTYPE_INVALID,  
    MPIControlMessageINTERRUPTS_DISABLED,
    MPIControlMessageEXTERNAL_MEMORY_OVERFLOW,
    MPIControlMessageADC_COUNT_INVALID,               
    MPIControlMessageAXIS_COUNT_INVALID,    
    MPIControlMessageCAPTURE_COUNT_INVALID,   
    MPIControlMessageCOMPARE_COUNT_INVALID,    
    MPIControlMessageCMDDAC_COUNT_INVALID,    
    MPIControlMessageAUXDAC_COUNT_INVALID,    
    MPIControlMessageFILTER_COUNT_INVALID,    
    MPIControlMessageMOTION_COUNT_INVALID,    
    MPIControlMessageMOTOR_COUNT_INVALID,  
} MPIControlMessage;

typedef enum {
    MEIControlMessageFIRMWARE_INVALID = MEIControlMessageLAST,
    MEIControlMessageFIRMWARE_VERSION,
} MEIControlMessage;