1.1 --- a/src/vid.c	Wed Dec 01 22:02:42 2010 +0200
     1.2 +++ b/src/vid.c	Thu Dec 02 08:45:41 2010 +0200
     1.3 @@ -1,26 +1,24 @@
     1.4  #include <string.h>
     1.5  #include "vid.h"
     1.6  
     1.7 -#define WIDTH	80
     1.8 -#define HEIGHT	25
     1.9  static uint16_t *vmem = (uint16_t*)0xb8000;
    1.10  
    1.11 -void clear_scr(void)
    1.12 +void clear_scr(int color)
    1.13  {
    1.14  	memset(vmem, 0, WIDTH * HEIGHT * 2);
    1.15  }
    1.16  
    1.17 -void set_cursor(int x, int y)
    1.18 +void set_char(char c, int x, int y, int fg, int bg)
    1.19  {
    1.20 -	if(x < 0 || x >= WIDTH || y < 0 || y >= HEIGHT) {
    1.21 -		/* disable cursor */
    1.22 -		return;
    1.23 -	}
    1.24 -	/* set cursor position */
    1.25 +	uint16_t attr = (fg & 0xf) | ((bg & 7) << 4);
    1.26 +	vmem[y * WIDTH + x] = (uint16_t)c | (attr << 8);
    1.27  }
    1.28  
    1.29 -void put_char(char c, int x, int y, int fg, int bg)
    1.30 +void scroll_scr(void)
    1.31  {
    1.32 -	uint16_t attr = (fg & 0xf) | ((bg & 7) << 4);
    1.33 -	vmem[y * 80 + x] = (uint16_t)c | (attr << 8);
    1.34 +	/* copy the second up to last text line, one line back, then
    1.35 +	 * clear the last line.
    1.36 +	 */
    1.37 +	memmove(vmem, vmem + WIDTH, WIDTH * (HEIGHT - 1) * 2);
    1.38 +	memset(vmem + WIDTH * (HEIGHT -1), 0, WIDTH * 2);
    1.39  }