C251 User's Guide

HBYTE

The HBYTE macro accesses individual bytes in the huge memory class.

The HBYTE macro is defined as:

#define HBYTE ((unsigned char volatile huge  *)0)  /* HDATA memory   */

You may use this macro in your programs as follows:

#include <absacc.h>       /* include absolute memory access macros      */
   :
   :
rval = HBYTE [0x0002];    /* read contents of HDATA memory at 0002H     */

#define IO HBYTE[0x8000]  /* define IO as address 0x8000 in near memory */
if (IO) IO = 0;           /* test address 008000H and assign a value    */

unsigned long address;
HBYTE[address] = 0;       /* set memory at location address to 0        */