POKE 1,0 would mess up the bank switching of addresses above $A000 and switch on the Datasette motor. Probably not what you wanted. I guess you meant POKE 646,1 (white text on black screen).
I memory serves me the sequence turns the screen black and POKE 1,0 hangs it. At least that is what I intended, maybe it was POKE 0,1?
I memory serves me the sequence turns the screen black and POKE 1,0 hangs it. At least that is what I intended, maybe it was POKE 0,1?