( screen )

:dev/r fff8 ( std read port )
:dev/w fff9 ( std write port )

;width 2 ;height 2

|0100 @RESET 
	
	( set read/write to dev/screen )
	#01 DUP =dev/r =dev/w 

	( load screen size )
	#00 IOR2 =width
	#02 IOR2 =height

	( draw pixel at screen center )
	#0101 
	~width #0002 DIV2 
	~height #0002 DIV2 
	,putpixel JSR

BRK

|c000 @FRAME BRK

@putpixel 
	IOW2 ( y short )
	IOW2 ( x short )
	IOW ( color byte )
	IOW ( redraw byte )
	RTS

|d000 @ERROR BRK 
|FFFA .RESET .FRAME .ERROR