31 lines
726 B
C
31 lines
726 B
C
|
/*
|
||
|
|
SCREENPL.C - This example shows how to write directly
|
||
|
|
to screen memory under the Phar Lap DOS extender.
|
||
|
|
|
||
|
|
Compile & Link: wcl386 /l=pharlap SCREENPL
|
||
|
|
*/
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <dos.h>
|
||
|
|
|
||
|
|
/*
|
||
|
|
Phar Lap allows access to screen memory through a
|
||
|
|
special selector. Refer to "Hardware Access" in
|
||
|
|
Phar Lap's documentation for details.
|
||
|
|
*/
|
||
|
|
#define PL_SCREEN_SELECTOR 0x1c
|
||
|
|
#define SCREEN_SIZE 80*25
|
||
|
|
|
||
|
|
void main()
|
||
|
|
{
|
||
|
|
/* Need a far pointer to use the screen selector */
|
||
|
|
char far *ptr;
|
||
|
|
int i;
|
||
|
|
|
||
|
|
/* Make a far pointer to screen memory */
|
||
|
|
ptr = MK_FP( PL_SCREEN_SELECTOR, 0 );
|
||
|
|
for( i = 0; i < SCREEN_SIZE - 1; i++ ) {
|
||
|
|
*ptr = '*';
|
||
|
|
ptr += 2 * sizeof( char );
|
||
|
|
}
|
||
|
|
}
|