.model small
.386
.stack
.data
			toprow  equ  0000h
			rgtcol  equ  0280h
			letcol  equ  0000h
			botrow  equ  01e0h
			colorf  db ?
			colorb  db ?
.code
.startup
 			mov ah,0fh
 			mov bh,0
 			int 10h
 			
 			push ax 			
 			mov ah,0
 			mov al,12h
 			int 10h
 			mov colorb,00h
 			mov colorf,05h
 			mov bh,0
 			mov ah,0bh
 			mov bl,colorb
 			int 10h
 			mov dx,200
 			mov cx,200
 			mov ah,0ch
 			mov al,colorf
 			int 10h
 			
ready:	mov ah,10h
				int 16h
				cmp ah,01h
				je stop
				cmp ah,3bh
				je bset
				cmp ah,3ch
				je fset
				cmp ah,4dh
				je draw1
				cmp ah,4bh
				je draw2
				cmp ah,48h
				je draw3
				cmp ah,50h
				je draw4
				jmp ready
				
bset:	inc colorb
			mov ah,0bh
			mov bl,colorb
			mov bh,0
			int 10h
			jmp ready
			
fset: inc colorf
			jmp ready
			
draw1: inc cx
			 cmp cx,rgtcol
			 jg sdr1
			 jmp disp
			 
sdr1:	 dec cx
			 jmp ready
			 
draw2:	dec cx
				cmp cx,letcol
				jl  sdr2
				jmp disp
				
sdr2:		inc cx
				jmp ready							 			 										
				
draw3:	dec dx
				cmp dx,toprow
				jl sdr3		
				jmp disp
				
sdr3:  inc dx
				jmp ready
				
draw4: inc dx
				cmp dx,botrow
				jg sdr4
				jmp disp
				
sdr4:		dec dx
				jmp ready
				
disp:		mov bl,colorf
				mov ah,0ch
				mov al,colorf
				int 10h
				jmp ready
				
stop:  pop ax
				mov ah,0
				int 10h
.exit 0
end