🚀 go-pugleaf

rwallace@unix1.tcd.ie (russell wallace) writes:

>Basically the method of accessing screen memory I'm using is with a far
>pointer with segment = B800h and offset = row*160 + column*2, to give a
>pointer to the character+attribute at (row,column). This works fine in
>tiny, small, large etc. memory models, but does not work in extended
>(option mx) memory model - as soon as I try to write a value into the

The following should work:

#include <dos.h> /* For the declaration of _x386_zero_base_selector. */
		 /* Also, MK_FP() is prototyped. */
int main()
{
  char _far *screen_ptr = MK_FP(_x386_zero_base_selector, 0xb800);

  /* Now use the screen_ptr as you normally would, it points to the base
     address of the start of the screen. */

  /* If you get the X-32VM extender (the successor to DOSX) from FlashTek,
  there is a near pointer that points to the start of memory 0000:0000 that
  you could also use for somewhat faster access.   It is called 
  _x32_zero_base_pointer (or ptr, I forget right now). */
}

Send me email if you still are having problems...

Joe Huffman
FlashTek, Inc.                  FlashTek, Ltd.
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