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Well I was just playin around a bit with the Video Modes and suddenly noticed that the program didnt quit Mode13h, as soon as the program drew a couple of pixels. Can anybody tell me why?

Heres the source code:

.MODEL SMALL

.DATA

Count 	dw	10



.STACK 128



.CODE

VGA:	mov ah,0

	mov al,19

	int 10h		;Interrupt 10h - Mode 13h

	

	mov cx,23

	mov dx,23

Pixel:	mov ah,0Ch

	mov al,9

	int 10h		;Pixel Plotting

	inc cx		;change x-coordinate

	inc dx		;change y-coordinate

	dec count

	cmp count,0

	je Delay

	jne Pixel

	

;Hold:	xor ah,ah	;waits for keyboard input, wrote this so i had time to 

;	mov ah,1	;look at the pixels

;	int 21



Delay:	mov cx,5

	loop Delay

	

Exit:	xor ah,ah

	mov ah,4Ch

	int 21



END VGA

My memories of DOS are intentionally getting dim but Chimpface is right, the video mode will stay at what you set until it is changed back again by either yours or another program.

Just another int10h call.

Regards,

hutch@movsd.com