Implementing Direct Memory Access (DMA) in C

Listing 5 (labmastr.c) Basic Routines Required for Programming the Lab Master AD

/*****************************************************

       Copyright Don Bradley, 1991.

       Permission is granted for used of these routines
       in any manner as long as this copyright notice is
       included.

       Tested using Quick C 2.5 and MSC 6.0 on a
       Toshiba T5200.

*****************************************************/

#include <conio.h>

#include "labmastr.h"

int LabMasterAD_Enable()
/*& Enables the Labmaster AD card. Returns Enable
        Status. */
       {
       if(LabMasterAD_Product() != LM_ID)
              return (0);

       outp(BRD_ENABLE, 1);
       return (inp(BRD_ENABLE) & 1);
       }

int LabMasterAD_Disable()
/*& Disables the Labmaster AD card. Returns Enable
        Status. */
       {
       outp(BRD_ENABLE, 0);
       return (inp(BRD_ENABLE) & 1);
       }

int LabMasterAD_Product()
/*& Returns the Labmaster AD Product Code */
       {
       return (inp(PRODUCT));
       }

int LabMasterAD_Version()
/*& Returns the Labmaster AD Version Number */
       {
       return (inp(VERSION));
       }

/* End of File */