Listing 1 mpu.h

#pragma pack(4)
struct mpustuff {
  int opsize;   /* # of bytes in operand */
  int ressize;  /* # of bytes expected back */
  char *opbuf;  /* operands */
  char *resbuf; /* return buffer */
};
#pragma pack()

/*
 * MPU commands. Only a few are listed here.
 */

#define  MPU_RESET     0xff
#define  MPU_VERSION   0xac
#define  MPU_REVISION  0xad
#define  MPU_UART      0x3f

/*
 * Driver commands
 */

#define MPU_DRIVERID  0x0100
#define MPU_GETDEBUG  0x0101
#define MPU_SETDEBUG  0x0102

/* End of File */