scr 	START 0
	LDCH txt
	+STCH screen
	LDX	#3
	+STCH screen, X	

	JSUB scrcfill

	JSUB scrclear

halt 	J halt 

scrclear LDCH #0
	LDS #scrlen
	LDX #0
loop	+STCH screen, X
	TIXR S 
	JLT loop

	RSUB


scrcfill
	LDS #scrlen
	LDX #0
loop2	+STCH screen, X
	TIXR S 
	JLT loop2

	RSUB

txt BYTE C'hi'
screen EQU 0x0B800
scrcols EQU 80
scrrows EQU 25
scrlen EQU 2000

	END scr